diff --git a/src/d_main.c b/src/d_main.c
index 29a91686..5cf95f4b 100644
--- a/src/d_main.c
+++ b/src/d_main.c
@@ -1162,7 +1162,7 @@ void D_SRB2Main(void)
 				if (s) // Check for NULL?
 				{
 					if (!W_VerifyNMUSlumps(s))
-						G_SetGameModified(true);
+						G_SetGameModified(true, false);
 					D_AddFile(s);
 				}
 			}
@@ -1189,7 +1189,7 @@ void D_SRB2Main(void)
 		else
 		{
 			if (!M_CheckParm("-server"))
-				G_SetGameModified(true);
+				G_SetGameModified(true, true);
 			autostart = true;
 		}
 	}
diff --git a/src/d_netcmd.c b/src/d_netcmd.c
index d8c81f65..6df7718e 100644
--- a/src/d_netcmd.c
+++ b/src/d_netcmd.c
@@ -2209,10 +2209,12 @@ static void Command_Map_f(void)
 		return;
 	}
 
-	if (!(netgame || multiplayer) && (!modifiedgame || savemoddata))
+	if (!(netgame || multiplayer) && !majormods)
 	{
 		if (COM_CheckParm("-force"))
-			G_SetGameModified(false);
+		{
+			G_SetGameModified(false, true);
+		}
 		else
 		{
 			CONS_Printf(M_GetText("Sorry, level change disabled in single player.\n"));
@@ -3791,7 +3793,7 @@ static void Command_RunSOC(void)
 		if (!P_RunSOC(fn))
 			CONS_Printf(M_GetText("Could not find SOC.\n"));
 		else
-			G_SetGameModified(multiplayer);
+			G_SetGameModified(multiplayer, false);
 		return;
 	}
 
@@ -3845,7 +3847,7 @@ static void Got_RunSOCcmd(UINT8 **cp, INT32 playernum)
 	}
 
 	P_RunSOC(filename);
-	G_SetGameModified(true);
+	G_SetGameModified(true, false);
 }
 
 /** Adds a pwad at runtime.
@@ -3882,7 +3884,7 @@ static void Command_Addfile(void)
 			CONS_Printf(M_GetText("Only the server or a remote admin can use this.\n"));
 			return;
 		}
-		G_SetGameModified(multiplayer);
+		G_SetGameModified(multiplayer, false);
 	}
 
 	// Add file on your client directly if it is trivial, or you aren't in a netgame.
@@ -4128,7 +4130,7 @@ static void Got_Addfilecmd(UINT8 **cp, INT32 playernum)
 		return;
 	}
 
-	G_SetGameModified(true);
+	G_SetGameModified(true, false);
 }
 
 static void Command_ListWADS_f(void)
@@ -4485,7 +4487,7 @@ static void Ringslinger_OnChange(void)
 	}
 
 	if (cv_ringslinger.value) // Only if it's been turned on
-		G_SetGameModified(multiplayer);
+		G_SetGameModified(multiplayer, true);
 }
 
 static void Gravity_OnChange(void)
@@ -4506,7 +4508,7 @@ static void Gravity_OnChange(void)
 #endif
 
 	if (!CV_IsSetToDefault(&cv_gravity))
-		G_SetGameModified(multiplayer);
+		G_SetGameModified(multiplayer, true);
 	gravity = cv_gravity.value;
 }
 
@@ -4902,7 +4904,7 @@ static void Fishcake_OnChange(void)
 	// so don't make modifiedgame always on!
 	if (cv_debug)
 	{
-		G_SetGameModified(multiplayer);
+		G_SetGameModified(multiplayer, true);
 	}
 
 	else if (cv_debug != cv_fishcake.value)
@@ -4918,12 +4920,14 @@ static void Fishcake_OnChange(void)
   */
 static void Command_Isgamemodified_f(void)
 {
-	if (savemoddata)
-		CONS_Printf(M_GetText("modifiedgame is true, but you can save medal and record data in this mod.\n"));
+	if (majormods)
+		CONS_Printf("The game has been modified with major add-ons, so you cannot play Record Attack.\n");
+	else if (savemoddata)
+		CONS_Printf("The game has been modified with an add-on with its own save data, so you can play Record Attack and earn medals.\n");
 	else if (modifiedgame)
-		CONS_Printf(M_GetText("modifiedgame is true, extras will not be unlocked\n"));
+		CONS_Printf("The game has been modified with only minor add-ons. You can play Record Attack, earn medals and unlock extras.\n");
 	else
-		CONS_Printf(M_GetText("modifiedgame is false, you can unlock extras\n"));
+		CONS_Printf("The game has not been modified. You can play Record Attack, earn medals and unlock extras.\n");
 }
 
 static void Command_Cheats_f(void)
diff --git a/src/d_netfil.c b/src/d_netfil.c
index c7cfdbc1..99a05840 100644
--- a/src/d_netfil.c
+++ b/src/d_netfil.c
@@ -426,7 +426,7 @@ void CL_LoadServerFiles(void)
 		else if (fileneeded[i].status == FS_FOUND)
 		{
 			P_AddWadFile(fileneeded[i].filename);
-			G_SetGameModified(true);
+			G_SetGameModified(true, false);
 			fileneeded[i].status = FS_OPEN;
 		}
 		else if (fileneeded[i].status == FS_MD5SUMBAD)
diff --git a/src/dehacked.c b/src/dehacked.c
index b9e29bc4..0ad67ff0 100644
--- a/src/dehacked.c
+++ b/src/dehacked.c
@@ -21,6 +21,7 @@
 #include "w_wad.h"
 #include "m_menu.h"
 #include "m_misc.h"
+#include "filesrch.h" // for refreshdirmenu
 #include "f_finale.h"
 #include "dehacked.h"
 #include "st_stuff.h"
@@ -79,8 +80,6 @@ static powertype_t get_power(const char *word);
 boolean deh_loaded = false;
 static int dbg_line;
 
-static boolean gamedataadded = false;
-
 #ifdef DELFILE
 typedef struct undehacked_s
 {
@@ -602,6 +601,14 @@ done:
 	Z_Free(s);
 }
 
+static int freeslotusage[2][2] = {{0, 0}, {0, 0}}; // [S_, MT_][max, previous .wad's max]
+
+void DEH_UpdateMaxFreeslots(void)
+{
+	freeslotusage[0][1] = freeslotusage[0][0];
+	freeslotusage[1][1] = freeslotusage[1][0];
+}
+
 // TODO: Figure out how to do undolines for this....
 // TODO: Warnings for running out of freeslots
 static void readfreeslots(MYFILE *f)
@@ -664,6 +671,7 @@ static void readfreeslots(MYFILE *f)
 					if (!FREE_STATES[i]) {
 						FREE_STATES[i] = Z_Malloc(strlen(word)+1, PU_STATIC, NULL);
 						strcpy(FREE_STATES[i],word);
+						freeslotusage[0][0]++;
 						break;
 					}
 			}
@@ -673,6 +681,7 @@ static void readfreeslots(MYFILE *f)
 					if (!FREE_MOBJS[i]) {
 						FREE_MOBJS[i] = Z_Malloc(strlen(word)+1, PU_STATIC, NULL);
 						strcpy(FREE_MOBJS[i],word);
+						freeslotusage[1][0]++;
 						break;
 					}
 			}
@@ -3139,6 +3148,7 @@ static void readmaincfg(MYFILE *f)
 				strlcpy(gamedatafilename, word2, sizeof (gamedatafilename));
 				strlwr(gamedatafilename);
 				savemoddata = true;
+				majormods = false;
 
 				// Also save a time attack folder
 				filenamelen = strlen(gamedatafilename)-4;  // Strip off the extension
@@ -3151,7 +3161,7 @@ static void readmaincfg(MYFILE *f)
 				// can't use sprintf since there is %u in savegamename
 				strcatbf(savegamename, srb2home, PATHSEP);
 
-				gamedataadded = true;
+				refreshdirmenu |= REFRESHDIR_GAMEDATA;
 			}
 			else if (fastcmp(word, "RESETDATA"))
 			{
@@ -3382,8 +3392,6 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 	for (i = 0; i < NUMSFX; i++)
 		savesfxnames[i] = S_sfx[i].name;
 
-	gamedataadded = false;
-
 	// it doesn't test the version of SRB2 and version of dehacked file
 	dbg_line = -1; // start at -1 so the first line is 0.
 	while (!myfeof(f))
@@ -3417,10 +3425,12 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 			if (fastcmp(word, "FREESLOT"))
 			{
 				readfreeslots(f);
+				// This is not a major mod.
 				continue;
 			}
 			else if (fastcmp(word, "MAINCFG"))
 			{
+				G_SetGameModified(multiplayer, true);
 				readmaincfg(f);
 				DEH_WriteUndoline(word, "", UNDO_HEADER);
 				continue;
@@ -3429,6 +3439,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 			{
 				readwipes(f);
 				DEH_WriteUndoline(word, "", UNDO_HEADER);
+				// This is not a major mod.
 				continue;
 			}
 			word2 = strtok(NULL, " ");
@@ -3449,6 +3460,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 					ignorelines(f);
 				}
 				DEH_WriteUndoline(word, word2, UNDO_HEADER);
+				// This is not a major mod.
 				continue;
 			}
 			if (word2)
@@ -3462,19 +3474,25 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 					// Read texture from spec file.
 					readtexture(f, word2);
 					DEH_WriteUndoline(word, word2, UNDO_HEADER);
+					// This is not a major mod.
 				}
 				else if (fastcmp(word, "PATCH"))
 				{
 					// Read patch from spec file.
 					readpatch(f, word2, wad);
 					DEH_WriteUndoline(word, word2, UNDO_HEADER);
+					// This is not a major mod.
 				}
 				else if (fastcmp(word, "THING") || fastcmp(word, "MOBJ") || fastcmp(word, "OBJECT"))
 				{
 					if (i == 0 && word2[0] != '0') // If word2 isn't a number
 						i = get_mobjtype(word2); // find a thing by name
 					if (i < NUMMOBJTYPES && i >= 0)
+					{
+						if (i < (MT_FIRSTFREESLOT+freeslotusage[1][1]))
+							G_SetGameModified(multiplayer, true); // affecting something earlier than the first freeslot allocated in this .wad? DENIED
 						readthing(f, i);
+					}
 					else
 					{
 						deh_warning("Thing %d out of range (0 - %d)", i, NUMMOBJTYPES-1);
@@ -3485,6 +3503,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 /*				else if (fastcmp(word, "ANIMTEX"))
 				{
 					readAnimTex(f, i);
+					// This is not a major mod.
 				}*/
 				else if (fastcmp(word, "LIGHT"))
 				{
@@ -3498,6 +3517,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 						ignorelines(f);
 					}
 					DEH_WriteUndoline(word, word2, UNDO_HEADER);
+					// This is not a major mod.
 #endif
 				}
 				else if (fastcmp(word, "SPRITE"))
@@ -3513,6 +3533,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 						ignorelines(f);
 					}
 					DEH_WriteUndoline(word, word2, UNDO_HEADER);
+					// This is not a major mod.
 #endif
 				}
 				else if (fastcmp(word, "LEVEL"))
@@ -3525,7 +3546,11 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 						i = M_MapNumber(word2[0], word2[1]);
 
 					if (i > 0 && i <= NUMMAPS)
+					{
+						if (mapheaderinfo[i])
+							G_SetGameModified(multiplayer, true); // only mark as a major mod if it replaces an already-existing mapheaderinfo
 						readlevelheader(f, i);
+					}
 					else
 					{
 						deh_warning("Level number %d out of range (1 - %d)", i, NUMMAPS);
@@ -3543,13 +3568,18 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 						ignorelines(f);
 					}
 					DEH_WriteUndoline(word, word2, UNDO_HEADER);
+					//G_SetGameModified(multiplayer, true); -- might have to reconsider in a future update
 				}
 				else if (fastcmp(word, "FRAME") || fastcmp(word, "STATE"))
 				{
 					if (i == 0 && word2[0] != '0') // If word2 isn't a number
 						i = get_state(word2); // find a state by name
 					if (i < NUMSTATES && i >= 0)
+					{
+						if (i < (S_FIRSTFREESLOT+freeslotusage[0][1]))
+							G_SetGameModified(multiplayer, true); // affecting something earlier than the first freeslot allocated in this .wad? DENIED
 						readframe(f, i);
+					}
 					else
 					{
 						deh_warning("Frame %d out of range (0 - %d)", i, NUMSTATES-1);
@@ -3578,6 +3608,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 					}
 					else
 						deh_warning("pointer (Frame %d) : missing ')'", i);
+					G_SetGameModified(multiplayer, true);
 				}*/
 				else if (fastcmp(word, "SOUND"))
 				{
@@ -3591,6 +3622,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 						ignorelines(f);
 					}
 					DEH_WriteUndoline(word, word2, UNDO_HEADER);
+					// This is not a major mod.
 				}
 /*				else if (fastcmp(word, "SPRITE"))
 				{
@@ -3611,6 +3643,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 					}
 					else
 						deh_warning("Sprite %d doesn't exist",i);
+					// This is not a major mod.
 				}*/
 				else if (fastcmp(word, "HUDITEM"))
 				{
@@ -3624,10 +3657,11 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 						ignorelines(f);
 					}
 					DEH_WriteUndoline(word, word2, UNDO_HEADER);
+					// This is not a major mod.
 				}
 				else if (fastcmp(word, "EMBLEM"))
 				{
-					if (!gamedataadded)
+					if (!(refreshdirmenu & REFRESHDIR_GAMEDATA))
 					{
 						deh_warning("You must define a custom gamedata to use \"%s\"", word);
 						ignorelines(f);
@@ -3647,7 +3681,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 				}
 				else if (fastcmp(word, "EXTRAEMBLEM"))
 				{
-					if (!gamedataadded)
+					if (!(refreshdirmenu & REFRESHDIR_GAMEDATA))
 					{
 						deh_warning("You must define a custom gamedata to use \"%s\"", word);
 						ignorelines(f);
@@ -3667,7 +3701,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 				}
 				else if (fastcmp(word, "UNLOCKABLE"))
 				{
-					if (!gamedataadded)
+					if (!(refreshdirmenu & REFRESHDIR_GAMEDATA))
 					{
 						deh_warning("You must define a custom gamedata to use \"%s\"", word);
 						ignorelines(f);
@@ -3683,7 +3717,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 				}
 				else if (fastcmp(word, "CONDITIONSET"))
 				{
-					if (!gamedataadded)
+					if (!(refreshdirmenu & REFRESHDIR_GAMEDATA))
 					{
 						deh_warning("You must define a custom gamedata to use \"%s\"", word);
 						ignorelines(f);
@@ -3718,7 +3752,7 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 				{
 					boolean clearall = (fastcmp(word2, "ALL"));
 
-					if (!gamedataadded)
+					if (!(refreshdirmenu & REFRESHDIR_GAMEDATA))
 					{
 						deh_warning("You must define a custom gamedata to use \"%s\"", word);
 						continue;
@@ -3755,8 +3789,8 @@ static void DEH_LoadDehackedFile(MYFILE *f, UINT16 wad)
 			deh_warning("No word in this line: %s", s);
 	} // end while
 
-	if (gamedataadded)
-		G_LoadGameData();
+	/*if (gamedataadded) -- REFRESHDIR_GAMEDATA murdered this
+		G_LoadGameData();*/
 
 	dbg_line = -1;
 	if (deh_num_warning)
@@ -9356,6 +9390,7 @@ static inline int lib_freeslot(lua_State *L)
 					CONS_Printf("State S_%s allocated.\n",word);
 					FREE_STATES[i] = Z_Malloc(strlen(word)+1, PU_STATIC, NULL);
 					strcpy(FREE_STATES[i],word);
+					freeslotusage[0][0]++;
 					lua_pushinteger(L, i);
 					r++;
 					break;
@@ -9371,6 +9406,7 @@ static inline int lib_freeslot(lua_State *L)
 					CONS_Printf("MobjType MT_%s allocated.\n",word);
 					FREE_MOBJS[i] = Z_Malloc(strlen(word)+1, PU_STATIC, NULL);
 					strcpy(FREE_MOBJS[i],word);
+					freeslotusage[1][0]++;
 					lua_pushinteger(L, i);
 					r++;
 					break;
@@ -9740,6 +9776,9 @@ static inline int lib_getenum(lua_State *L)
 	} else if (fastcmp(word,"modifiedgame")) {
 		lua_pushboolean(L, modifiedgame && !savemoddata);
 		return 1;
+	} else if (fastcmp(word,"majormods")) {
+		lua_pushboolean(L, majormods);
+		return 1;
 	} else if (fastcmp(word,"menuactive")) {
 		lua_pushboolean(L, menuactive);
 		return 1;
diff --git a/src/dehacked.h b/src/dehacked.h
index 683fe7d9..0d6cc902 100644
--- a/src/dehacked.h
+++ b/src/dehacked.h
@@ -37,6 +37,8 @@ void DEH_UnloadDehackedWad(UINT16 wad);
 void DEH_LoadDehackedLump(lumpnum_t lumpnum);
 void DEH_LoadDehackedLumpPwad(UINT16 wad, UINT16 lump);
 
+void DEH_UpdateMaxFreeslots(void);
+
 void DEH_Check(void);
 
 fixed_t get_number(const char *word);
diff --git a/src/doomstat.h b/src/doomstat.h
index 6d710e28..9ae2726d 100644
--- a/src/doomstat.h
+++ b/src/doomstat.h
@@ -54,6 +54,7 @@ extern boolean gamecomplete;
 
 // Set if homebrew PWAD stuff has been added.
 extern boolean modifiedgame;
+extern boolean majormods;
 extern UINT16 mainwads;
 extern boolean savemoddata; // This mod saves time/emblem data.
 extern boolean disableSpeedAdjust; // Don't alter the duration of player states if true
@@ -280,6 +281,8 @@ typedef struct
 #define LF2_NIGHTSATTACK   8 ///< Show this map in NiGHTS mode menu
 #define LF2_NOVISITNEEDED 16 ///< Available in time attack/nights mode without visiting the level
 
+#define LF2_EXISTSHACK   128 ///< Map lump exists; as noted, a single-bit hack that can be freely movable to other variables without concern.
+
 // Save override
 #define SAVE_NEVER   -1
 #define SAVE_DEFAULT  0
diff --git a/src/filesrch.h b/src/filesrch.h
index 4186271b..01a52848 100644
--- a/src/filesrch.h
+++ b/src/filesrch.h
@@ -88,7 +88,8 @@ typedef enum
 	REFRESHDIR_WARNING = 4,
 	REFRESHDIR_ERROR = 8,
 	REFRESHDIR_NOTLOADED = 16,
-	REFRESHDIR_MAX = 32
+	REFRESHDIR_MAX = 32,
+	REFRESHDIR_GAMEDATA = 64
 } refreshdir_enum;
 
 void closefilemenu(boolean validsize);
diff --git a/src/g_game.c b/src/g_game.c
index ee004b64..5014e781 100644
--- a/src/g_game.c
+++ b/src/g_game.c
@@ -16,6 +16,7 @@
 #include "d_main.h"
 #include "d_player.h"
 #include "f_finale.h"
+#include "filesrch.h" // for refreshdirmenu
 #include "p_setup.h"
 #include "p_saveg.h"
 #include "i_system.h"
@@ -86,7 +87,8 @@ INT16 lastmapsaved = 0; // Last map we auto-saved at
 boolean gamecomplete = false;
 
 UINT16 mainwads = 0;
-boolean modifiedgame; // Set if homebrew PWAD stuff has been added.
+boolean modifiedgame = false; // Set if homebrew PWAD stuff has been added.
+boolean majormods = false; // Set if Lua/Gameplay SOC/replacement map has been added.
 boolean savemoddata = false;
 UINT8 paused;
 UINT8 modeattacking = ATTACKING_NONE;
@@ -752,16 +754,21 @@ void G_SetNightsRecords(void)
 }*/
 
 // for consistency among messages: this modifies the game and removes savemoddata.
-void G_SetGameModified(boolean silent)
+void G_SetGameModified(boolean silent, boolean major)
 {
-	if (modifiedgame && !savemoddata)
+	if ((majormods && modifiedgame) || !mainwads || (refreshdirmenu & REFRESHDIR_GAMEDATA)) // new gamedata amnesty?
 		return;
 
 	modifiedgame = true;
-	savemoddata = false;
+
+	if (!major)
+		return;
+
+	//savemoddata = false; -- there is literally no reason to do this anymore.
+	majormods = true;
 
 	if (!silent)
-		CONS_Alert(CONS_NOTICE, M_GetText("Game must be restarted to record statistics.\n"));
+		CONS_Alert(CONS_NOTICE, M_GetText("Game must be restarted to play record attack.\n"));
 
 	// If in record attack recording, cancel it.
 	if (modeattacking)
@@ -3942,7 +3949,6 @@ void G_LoadGameData(void)
 // Saves the main data file, which stores information such as emblems found, etc.
 void G_SaveGameData(boolean force)
 {
-	const boolean wasmodified = modifiedgame;
 	size_t length;
 	INT32 i, j;
 	UINT8 btemp;
@@ -3959,9 +3965,7 @@ void G_SaveGameData(boolean force)
 		return;
 	}
 
-	if (force) // SRB2Kart: for enabling unlocks online, even if the game is modified
-		modifiedgame = savemoddata; // L-let's just sort of... hack around the cheat protection, because I'm too worried about just removing it @@;
-	else if (modifiedgame && !savemoddata)
+	if (majormods && !force)
 	{
 		free(savebuffer);
 		save_p = savebuffer = NULL;
@@ -3974,7 +3978,7 @@ void G_SaveGameData(boolean force)
 	WRITEUINT32(save_p, totalplaytime);
 	WRITEUINT32(save_p, matchesplayed);
 
-	btemp = (UINT8)(savemoddata || modifiedgame);
+	btemp = (UINT8)(savemoddata); // what used to be here was profoundly dunderheaded
 	WRITEUINT8(save_p, btemp);
 
 	// TODO put another cipher on these things? meh, I don't care...
@@ -4060,9 +4064,6 @@ void G_SaveGameData(boolean force)
 	FIL_WriteFile(va(pandf, srb2home, gamedatafilename), savebuffer, length);
 	free(savebuffer);
 	save_p = savebuffer = NULL;
-
-	if (force) // Eeeek, I'm sorry for my sins!
-		modifiedgame = wasmodified;
 }
 
 #define VERSIONSIZE 16
@@ -5921,6 +5922,32 @@ void G_DoPlayDemo(char *defdemoname)
 		return;
 	}
 
+	// Skin not loaded?
+	if (!SetPlayerSkin(0, skin))
+	{
+		snprintf(msg, 1024, M_GetText("%s features a character that is not currently loaded.\n"), pdemoname);
+		CONS_Alert(CONS_ERROR, "%s", msg);
+		M_StartMessage(msg, NULL, MM_NOTHING);
+		Z_Free(pdemoname);
+		Z_Free(demobuffer);
+		demoplayback = false;
+		titledemo = false;
+		return;
+	}
+
+	// ...*map* not loaded?
+	if (!gamemap || (gamemap > NUMMAPS) || !mapheaderinfo[gamemap-1] || !(mapheaderinfo[gamemap-1]->menuflags & LF2_EXISTSHACK))
+	{
+		snprintf(msg, 1024, M_GetText("%s features a course that is not currently loaded.\n"), pdemoname);
+		CONS_Alert(CONS_ERROR, "%s", msg);
+		M_StartMessage(msg, NULL, MM_NOTHING);
+		Z_Free(pdemoname);
+		Z_Free(demobuffer);
+		demoplayback = false;
+		titledemo = false;
+		return;
+	}
+
 	Z_Free(pdemoname);
 
 	memset(&oldcmd,0,sizeof(oldcmd));
@@ -5952,9 +5979,6 @@ void G_DoPlayDemo(char *defdemoname)
 	P_SetRandSeed(randseed);
 	G_InitNew(false, G_BuildMapName(gamemap), true, true); // Doesn't matter whether you reset or not here, given changes to resetplayer.
 
-	// Set skin
-	SetPlayerSkin(0, skin);
-
 	// Set color
 	for (i = 0; i < MAXSKINCOLORS; i++)
 		if (!stricmp(KartColor_Names[i],color))				// SRB2kart
@@ -6004,6 +6028,7 @@ void G_AddGhost(char *defdemoname)
 	UINT8 *buffer,*p;
 	mapthing_t *mthing;
 	UINT16 count, ghostversion;
+	skin_t *ghskin = &skins[0];
 
 	name[16] = '\0';
 	skin[16] = '\0';
@@ -6149,6 +6174,21 @@ void G_AddGhost(char *defdemoname)
 		return;
 	}
 
+	for (i = 0; i < numskins; i++)
+		if (!stricmp(skins[i].name,skin))
+		{
+			ghskin = &skins[i];
+			break;
+		}
+
+	if (i == numskins)
+	{
+		CONS_Alert(CONS_NOTICE, M_GetText("Failed to add ghost %s: Invalid character.\n"), pdemoname);
+		Z_Free(pdemoname);
+		Z_Free(buffer);
+		return;
+	}
+
 	gh = Z_Calloc(sizeof(demoghost), PU_LEVEL, NULL);
 	gh->next = ghosts;
 	gh->buffer = buffer;
@@ -6194,14 +6234,7 @@ void G_AddGhost(char *defdemoname)
 	gh->oldmo.z = gh->mo->z;
 
 	// Set skin
-	gh->mo->skin = &skins[0];
-	for (i = 0; i < numskins; i++)
-		if (!stricmp(skins[i].name,skin))
-		{
-			gh->mo->skin = &skins[i];
-			break;
-		}
-	gh->oldmo.skin = gh->mo->skin;
+	gh->mo->skin = gh->oldmo.skin = ghskin;
 
 	// Set color
 	gh->mo->color = ((skin_t*)gh->mo->skin)->prefcolor;
diff --git a/src/g_game.h b/src/g_game.h
index 6d11a4a0..fc7a4a4f 100644
--- a/src/g_game.h
+++ b/src/g_game.h
@@ -226,7 +226,7 @@ boolean G_GetRetryFlag(void);
 void G_LoadGameData(void);
 void G_LoadGameSettings(void);
 
-void G_SetGameModified(boolean silent);
+void G_SetGameModified(boolean silent, boolean major);
 
 void G_SetGamestate(gamestate_t newstate);
 
diff --git a/src/lua_script.c b/src/lua_script.c
index 34a26052..1f87d33e 100644
--- a/src/lua_script.c
+++ b/src/lua_script.c
@@ -212,6 +212,9 @@ void LUA_LoadLump(UINT16 wad, UINT16 lump)
 
 	LUA_LoadFile(&f, name); // actually load file!
 
+	// Okay, we've modified the game beyond the point of no return.
+	G_SetGameModified(multiplayer, true);
+
 	free(name);
 	Z_Free(f.data);
 }
diff --git a/src/m_cheat.c b/src/m_cheat.c
index 38d8cc7a..2fc2e85c 100644
--- a/src/m_cheat.c
+++ b/src/m_cheat.c
@@ -121,7 +121,7 @@ static UINT8 cheatf_devmode(void)
 	S_StartSound(0, sfx_itemup);
 
 	// Just unlock all the things and turn on -debug and console devmode.
-	G_SetGameModified(false);
+	G_SetGameModified(false, false); // might need to revist the latter later
 	for (i = 0; i < MAXUNLOCKABLES; i++)
 		unlockables[i].unlocked = true;
 	devparm = true;
@@ -295,7 +295,7 @@ void Command_CheatNoClip_f(void)
 	plyr->pflags ^= PF_NOCLIP;
 	CONS_Printf(M_GetText("No Clipping %s\n"), plyr->pflags & PF_NOCLIP ? M_GetText("On") : M_GetText("Off"));
 
-	G_SetGameModified(multiplayer);
+	G_SetGameModified(multiplayer, true);
 }
 
 void Command_CheatGod_f(void)
@@ -310,7 +310,7 @@ void Command_CheatGod_f(void)
 	plyr->pflags ^= PF_GODMODE;
 	CONS_Printf(M_GetText("Sissy Mode %s\n"), plyr->pflags & PF_GODMODE ? M_GetText("On") : M_GetText("Off"));
 
-	G_SetGameModified(multiplayer);
+	G_SetGameModified(multiplayer, true);
 }
 
 void Command_CheatNoTarget_f(void)
@@ -325,7 +325,7 @@ void Command_CheatNoTarget_f(void)
 	plyr->pflags ^= PF_INVIS;
 	CONS_Printf(M_GetText("SEP Field %s\n"), plyr->pflags & PF_INVIS ? M_GetText("On") : M_GetText("Off"));
 
-	G_SetGameModified(multiplayer);
+	G_SetGameModified(multiplayer, true);
 }
 
 void Command_Scale_f(void)
@@ -727,7 +727,7 @@ void Command_Devmode_f(void)
 		return;
 	}
 
-	G_SetGameModified(multiplayer);
+	G_SetGameModified(multiplayer, true);
 }
 
 /*void Command_Setrings_f(void)
@@ -1267,7 +1267,7 @@ void Command_ObjectPlace_f(void)
 	REQUIRE_SINGLEPLAYER;
 	REQUIRE_NOULTIMATE;
 
-	G_SetGameModified(multiplayer);
+	G_SetGameModified(multiplayer, true);
 
 	// Entering objectplace?
 	if (!objectplacing)
diff --git a/src/m_cond.c b/src/m_cond.c
index 35eccd1c..b777e7d2 100644
--- a/src/m_cond.c
+++ b/src/m_cond.c
@@ -385,8 +385,7 @@ UINT8 M_UpdateUnlockablesAndExtraEmblems(boolean force)
 	char cechoText[992] = "";
 	UINT8 cechoLines = 0;
 
-	if (modifiedgame && !savemoddata
-		&& !force) // SRB2Kart: for enabling unlocks online in modified servers
+	if (majormods && !force) // SRB2Kart: for enabling unlocks online in modified servers
 		return false;
 
 	M_CheckUnlockConditions();
diff --git a/src/m_menu.c b/src/m_menu.c
index f0831a17..ee94ab3c 100644
--- a/src/m_menu.c
+++ b/src/m_menu.c
@@ -274,14 +274,13 @@ static menu_t SP_TimeAttackDef, SP_ReplayDef, SP_GuestReplayDef, SP_GhostDef;
 #ifndef NONET
 static void M_StartServerMenu(INT32 choice);
 static void M_ConnectMenu(INT32 choice);
-#endif
-static void M_StartOfflineServerMenu(INT32 choice);
-static void M_StartServer(INT32 choice);
-#ifndef NONET
+static void M_ConnectMenuModChecks(INT32 choice);
 static void M_Refresh(INT32 choice);
 static void M_Connect(INT32 choice);
 static void M_ChooseRoom(INT32 choice);
 #endif
+static void M_StartOfflineServerMenu(INT32 choice);
+static void M_StartServer(INT32 choice);
 static void M_SetupMultiPlayer(INT32 choice);
 static void M_SetupMultiPlayer2(INT32 choice);
 static void M_SetupMultiPlayer3(INT32 choice);
@@ -935,11 +934,11 @@ static menuitem_t MP_MainMenu[] =
 
 	{IT_HEADER, NULL, "Join a game", NULL, 132-24},
 #ifndef NONET
-	{IT_STRING|IT_CALL,       NULL, "Internet server browser...",M_ConnectMenu,            142-24},
+	{IT_STRING|IT_CALL,       NULL, "Internet server browser...",M_ConnectMenuModChecks,   142-24},
 	{IT_STRING|IT_KEYHANDLER, NULL, "Specify IPv4 address:",     M_HandleConnectIP,        150-24},
 #else
-	{IT_GRAYEDOUT,            NULL, "Internet server browser...",M_ConnectMenu,            142-24},
-	{IT_GRAYEDOUT,            NULL, "Specify IPv4 address:",     M_HandleConnectIP,        150-24},
+	{IT_GRAYEDOUT,            NULL, "Internet server browser...",NULL,                     142-24},
+	{IT_GRAYEDOUT,            NULL, "Specify IPv4 address:",     NULL,                     150-24},
 #endif
 	//{IT_HEADER, NULL, "Player setup", NULL, 80},
 	//{IT_STRING|IT_CALL,       NULL, "Name, character, color...", M_SetupMultiPlayer,       90},
@@ -2739,10 +2738,10 @@ boolean M_Responder(event_t *ev)
 				 || (currentMenu->menuitems[itemOn].status & IT_TYPE)==IT_SUBMENU)
                  && (currentMenu->menuitems[itemOn].status & IT_CALLTYPE))
 				{
-					if (((currentMenu->menuitems[itemOn].status & IT_CALLTYPE) & IT_CALL_NOTMODIFIED) && modifiedgame && !savemoddata)
+					if (((currentMenu->menuitems[itemOn].status & IT_CALLTYPE) & IT_CALL_NOTMODIFIED) && majormods)
 					{
 						S_StartSound(NULL, sfx_menu1);
-						M_StartMessage(M_GetText("This cannot be done with add-ons\nor in a cheated game.\n\n(Press a key)\n"), NULL, MM_NOTHING);
+						M_StartMessage(M_GetText("This cannot be done with complex add-ons\nor in a cheated game.\n\n(Press a key)\n"), NULL, MM_NOTHING);
 						return true;
 					}
 				}
@@ -4527,9 +4526,14 @@ static char *M_AddonsHeaderPath(void)
 #define CLEARNAME Z_Free(refreshdirname);\
 					refreshdirname = NULL
 
+static boolean prevmajormods = false;
+
 static void M_AddonsClearName(INT32 choice)
 {
-	CLEARNAME;
+	if (!majormods || prevmajormods)
+	{
+		CLEARNAME;
+	}
 	M_StopMessage(choice);
 }
 
@@ -4539,10 +4543,17 @@ static boolean M_AddonsRefresh(void)
 	if ((refreshdirmenu & REFRESHDIR_NORMAL) && !preparefilemenu(true))
 	{
 		UNEXIST;
+		if (refreshdirname)
+		{
+			CLEARNAME;
+		}
 		return true;
 	}
 
-	if (refreshdirmenu & REFRESHDIR_ADDFILE)
+	if (!majormods && prevmajormods)
+		prevmajormods = false;
+
+	if ((refreshdirmenu & REFRESHDIR_ADDFILE) || (majormods && !prevmajormods))
 	{
 		char *message = NULL;
 
@@ -4550,7 +4561,7 @@ static boolean M_AddonsRefresh(void)
 		{
 			S_StartSound(NULL, sfx_s26d);
 			if (refreshdirmenu & REFRESHDIR_MAX)
-				message = va("%c%s\x80\nMaximum number of add-ons reached.\nA file could not be loaded.\nIf you want to play with this add-on, restart the game to clear existing ones.\n\n(Press a key)\n", ('\x80' + (highlightflags>>V_CHARCOLORSHIFT)), refreshdirname);
+				message = va("%c%s\x80\nMaximum number of add-ons reached.\nA file could not be loaded.\nif you wish to play with this add-on, restart the game to clear existing ones.\n\n(Press a key)\n", ('\x80' + (highlightflags>>V_CHARCOLORSHIFT)), refreshdirname);
 			else
 				message = va("%c%s\x80\nA file was not loaded.\nCheck the console log for more information.\n\n(Press a key)\n", ('\x80' + (highlightflags>>V_CHARCOLORSHIFT)), refreshdirname);
 		}
@@ -4559,6 +4570,12 @@ static boolean M_AddonsRefresh(void)
 			S_StartSound(NULL, sfx_s224);
 			message = va("%c%s\x80\nA file was loaded with %s.\nCheck the console log for more information.\n\n(Press a key)\n", ('\x80' + (highlightflags>>V_CHARCOLORSHIFT)), refreshdirname, ((refreshdirmenu & REFRESHDIR_ERROR) ? "errors" : "warnings"));
 		}
+		else if (majormods && !prevmajormods)
+		{
+			S_StartSound(NULL, sfx_s221);
+			message = va("%c%s\x80\nGameplay has now been modified.\nif you wish to play record attack mode, restart the game to clear existing add-ons.\n\n(Press a key)\n", ('\x80' + (highlightflags>>V_CHARCOLORSHIFT)), refreshdirname);
+			prevmajormods = majormods;
+		}
 
 		if (message)
 		{
@@ -4709,7 +4726,7 @@ static void M_DrawAddons(void)
 	V_DrawSmallScaledPatch(x, y + 4, (menusearch[0] ? 0 : V_TRANSLUCENT), addonsp[NUM_EXT+3]);
 
 	x = BASEVIDWIDTH - x - 16;
-	V_DrawSmallScaledPatch(x, y + 4, ((!modifiedgame || savemoddata) ? 0 : V_TRANSLUCENT), addonsp[NUM_EXT+4]);
+	V_DrawSmallScaledPatch(x, y + 4, ((!majormods) ? 0 : V_TRANSLUCENT), addonsp[NUM_EXT+4]);
 
 	if (modifiedgame)
 		V_DrawSmallScaledPatch(x, y + 4, 0, addonsp[NUM_EXT+2]);
@@ -5106,7 +5123,7 @@ static void M_GetAllEmeralds(INT32 choice)
 	emeralds = ((EMERALD7)*2)-1;
 	M_StartMessage(M_GetText("You now have all 7 emeralds.\nUse them wisely.\nWith great power comes great ring drain.\n"),NULL,MM_NOTHING);
 
-	G_SetGameModified(multiplayer);
+	G_SetGameModified(multiplayer, true);
 }
 
 static void M_DestroyRobotsResponse(INT32 ch)
@@ -5117,7 +5134,7 @@ static void M_DestroyRobotsResponse(INT32 ch)
 	// Destroy all robots
 	P_DestroyRobots();
 
-	G_SetGameModified(multiplayer);
+	G_SetGameModified(multiplayer, true);
 }
 
 static void M_DestroyRobots(INT32 choice)
@@ -7384,6 +7401,20 @@ static void M_ConnectMenu(INT32 choice)
 	M_Refresh(0);
 }
 
+static void M_ConnectMenuModChecks(INT32 choice)
+{
+	(void)choice;
+	// okay never mind we want to COMMUNICATE to the player pre-emptively instead of letting them try and then get confused when it doesn't work
+
+	if (modifiedgame)
+	{
+		M_StartMessage(M_GetText("Add-ons are currently loaded.\n\nYou will only be able to join a server if\nit has the same ones loaded in the same order, which may be unlikely.\n\nIf you wish to play on other servers,\nrestart the game to clear existing add-ons.\n\n(Press a key)\n"),M_ConnectMenu,MM_EVENTHANDLER);
+		return;
+	}
+
+	M_ConnectMenu(-1);
+}
+
 static UINT32 roomIds[NUM_LIST_ROOMS];
 
 static void M_RoomMenu(INT32 choice)
diff --git a/src/p_map.c b/src/p_map.c
index c307e572..051a1e6f 100644
--- a/src/p_map.c
+++ b/src/p_map.c
@@ -3231,129 +3231,6 @@ isblocking:
 	return false; // stop
 }
 
-//
-// P_IsClimbingValid
-//
-// Unlike P_DoClimbing, don't use when up against a one-sided linedef.
-//
-static boolean P_IsClimbingValid(player_t *player, angle_t angle)
-{
-	fixed_t platx, platy;
-	subsector_t *glidesector;
-	fixed_t floorz, ceilingz;
-
-	platx = P_ReturnThrustX(player->mo, angle, player->mo->radius + FixedMul(8*FRACUNIT, player->mo->scale));
-	platy = P_ReturnThrustY(player->mo, angle, player->mo->radius + FixedMul(8*FRACUNIT, player->mo->scale));
-
-	glidesector = R_PointInSubsector(player->mo->x + platx, player->mo->y + platy);
-
-#ifdef ESLOPE
-	floorz = glidesector->sector->f_slope ? P_GetZAt(glidesector->sector->f_slope, player->mo->x, player->mo->y) : glidesector->sector->floorheight;
-	ceilingz = glidesector->sector->c_slope ? P_GetZAt(glidesector->sector->c_slope, player->mo->x, player->mo->y) : glidesector->sector->ceilingheight;
-#else
-	floorz = glidesector->sector->floorheight;
-	ceilingz = glidesector->sector->ceilingheight;
-#endif
-
-	if (glidesector->sector != player->mo->subsector->sector)
-	{
-		boolean floorclimb = false;
-		fixed_t topheight, bottomheight;
-
-		if (glidesector->sector->ffloors)
-		{
-			ffloor_t *rover;
-			for (rover = glidesector->sector->ffloors; rover; rover = rover->next)
-			{
-				if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER))
-					continue;
-
-				topheight = *rover->topheight;
-				bottomheight = *rover->bottomheight;
-
-#ifdef ESLOPE
-				if (*rover->t_slope)
-					topheight = P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y);
-				if (*rover->b_slope)
-					bottomheight = P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y);
-#endif
-
-				floorclimb = true;
-
-				if (player->mo->eflags & MFE_VERTICALFLIP)
-				{
-					if ((topheight < player->mo->z + player->mo->height) && ((player->mo->z + player->mo->height + player->mo->momz) < topheight))
-					{
-						floorclimb = true;
-					}
-					if (topheight < player->mo->z) // Waaaay below the ledge.
-					{
-						floorclimb = false;
-					}
-					if (bottomheight > player->mo->z + player->mo->height - FixedMul(16*FRACUNIT,player->mo->scale))
-					{
-						floorclimb = false;
-					}
-				}
-				else
-				{
-					if ((bottomheight > player->mo->z) && ((player->mo->z - player->mo->momz) > bottomheight))
-					{
-						floorclimb = true;
-					}
-					if (bottomheight > player->mo->z + player->mo->height) // Waaaay below the ledge.
-					{
-						floorclimb = false;
-					}
-					if (topheight < player->mo->z + FixedMul(16*FRACUNIT,player->mo->scale))
-					{
-						floorclimb = false;
-					}
-				}
-
-				if (floorclimb)
-					break;
-			}
-		}
-
-		if (player->mo->eflags & MFE_VERTICALFLIP)
-		{
-			if ((floorz <= player->mo->z + player->mo->height)
-				&& ((player->mo->z + player->mo->height - player->mo->momz) <= floorz))
-				floorclimb = true;
-
-			if ((floorz > player->mo->z)
-				&& glidesector->sector->floorpic == skyflatnum)
-				return false;
-
-			if ((player->mo->z + player->mo->height - FixedMul(16*FRACUNIT,player->mo->scale) > ceilingz)
-				|| (player->mo->z + player->mo->height <= floorz))
-				floorclimb = true;
-		}
-		else
-		{
-			if ((ceilingz >= player->mo->z)
-				&& ((player->mo->z - player->mo->momz) >= ceilingz))
-				floorclimb = true;
-
-			if ((ceilingz < player->mo->z+player->mo->height)
-				&& glidesector->sector->ceilingpic == skyflatnum)
-				return false;
-
-			if ((player->mo->z + FixedMul(16*FRACUNIT,player->mo->scale) < ceilingz)
-				|| (player->mo->z >= ceilingz))
-				floorclimb = true;
-		}
-
-		if (!floorclimb)
-			return false;
-
-		return true;
-	}
-
-	return false;
-}
-
 //
 // PTR_SlideTraverse
 //
@@ -3407,117 +3284,7 @@ isblocking:
 			P_ProcessSpecialSector(slidemo->player, slidemo->subsector->sector, li->polyobj->lines[0]->backsector);
 	}
 
-	if (slidemo->player && (slidemo->player->pflags & PF_GLIDING || slidemo->player->climbing)
-		&& slidemo->player->charability == CA_GLIDEANDCLIMB)
-	{
-		line_t *checkline = li;
-		sector_t *checksector;
-		ffloor_t *rover;
-		fixed_t topheight, bottomheight;
-		boolean fofline = false;
-		INT32 side = P_PointOnLineSide(slidemo->x, slidemo->y, li);
-
-		if (!side && li->backsector)
-			checksector = li->backsector;
-		else
-			checksector = li->frontsector;
-
-		if (checksector->ffloors)
-		{
-			for (rover = checksector->ffloors; rover; rover = rover->next)
-			{
-				if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || (rover->flags & FF_BUSTUP))
-					continue;
-
-				topheight = *rover->topheight;
-				bottomheight = *rover->bottomheight;
-
-#ifdef ESLOPE
-				if (*rover->t_slope)
-					topheight = P_GetZAt(*rover->t_slope, slidemo->x, slidemo->y);
-				if (*rover->b_slope)
-					bottomheight = P_GetZAt(*rover->b_slope, slidemo->x, slidemo->y);
-#endif
-
-				if (topheight < slidemo->z)
-					continue;
-
-				if (bottomheight > slidemo->z + slidemo->height)
-					continue;
-
-				// Got this far, so I guess it's climbable. // TODO: Climbing check, also, better method to do this?
-				if (rover->master->flags & ML_TFERLINE)
-				{
-					size_t linenum = li-checksector->lines[0];
-					checkline = rover->master->frontsector->lines[0] + linenum;
-					fofline = true;
-				}
-
-				break;
-			}
-		}
-
-		// see about climbing on the wall
-		if (!(checkline->flags & ML_NOCLIMB))
-		{
-			boolean canclimb;
-			angle_t climbangle, climbline;
-			INT32 whichside = P_PointOnLineSide(slidemo->x, slidemo->y, li);
-
-			climbangle = climbline = R_PointToAngle2(li->v1->x, li->v1->y, li->v2->x, li->v2->y);
-
-			if (whichside) // on second side?
-				climbline += ANGLE_180;
-
-			climbangle += (ANGLE_90 * (whichside ? -1 : 1));
-
-			canclimb = (li->backsector ? P_IsClimbingValid(slidemo->player, climbangle) : true);
-
-			if (((!slidemo->player->climbing && abs((signed)(slidemo->angle - ANGLE_90 - climbline)) < ANGLE_45)
-			|| (slidemo->player->climbing == 1 && abs((signed)(slidemo->angle - climbline)) < ANGLE_135))
-			&& canclimb)
-			{
-				slidemo->angle = climbangle;
-				if (!demoplayback || P_AnalogMove(slidemo->player))
-				{
-					if (slidemo->player == &players[consoleplayer])
-						localangle = slidemo->angle;
-					else if (slidemo->player == &players[secondarydisplayplayer])
-						localangle2 = slidemo->angle;
-					else if (slidemo->player == &players[thirddisplayplayer])
-						localangle3 = slidemo->angle;
-					else if (slidemo->player == &players[fourthdisplayplayer])
-						localangle4 = slidemo->angle;
-				}
-
-				if (!slidemo->player->climbing)
-				{
-					S_StartSound(slidemo->player->mo, sfx_s3k4a);
-					slidemo->player->climbing = 5;
-				}
-
-				slidemo->player->pflags &= ~(PF_GLIDING|PF_SPINNING|PF_JUMPED|PF_THOKKED);
-				slidemo->player->glidetime = 0;
-				slidemo->player->secondjump = 0;
-
-				if (slidemo->player->climbing > 1)
-					slidemo->momz = slidemo->momx = slidemo->momy = 0;
-
-				if (fofline)
-					whichside = 0;
-
-				if (!whichside)
-				{
-					slidemo->player->lastsidehit = checkline->sidenum[whichside];
-					slidemo->player->lastlinehit = (INT16)(checkline - lines);
-				}
-
-				P_Thrust(slidemo, slidemo->angle, FixedMul(5*FRACUNIT, slidemo->scale));
-			}
-		}
-	}
-
-	if (in->frac < bestslidefrac && (!slidemo->player || !slidemo->player->climbing))
+	if (in->frac < bestslidefrac)
 	{
 		secondslidefrac = bestslidefrac;
 		secondslideline = bestslideline;
diff --git a/src/p_mobj.c b/src/p_mobj.c
index f71ff209..d380b97a 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -3233,8 +3233,7 @@ boolean P_CanRunOnWater(player_t *player, ffloor_t *rover)
 #endif
 		*rover->topheight;
 
-	if (!(player->pflags & PF_NIGHTSMODE) && !player->homing
-		&& (((player->charability == CA_SWIM) || player->powers[pw_super] || player->charflags & SF_RUNONWATER) && player->mo->ceilingz-topheight >= player->mo->height)
+	if (((player->charflags & SF_RUNONWATER) && player->mo->ceilingz-topheight >= player->mo->height)
 		&& (rover->flags & FF_SWIMMABLE) && !(player->pflags & PF_SPINNING) && player->speed > FixedMul(player->runspeed, player->mo->scale)
 		&& !(player->pflags & PF_SLIDING)
 		&& abs(player->mo->z - topheight) < FixedMul(30*FRACUNIT, player->mo->scale))
diff --git a/src/p_setup.c b/src/p_setup.c
index 49b22184..912791cf 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -234,7 +234,7 @@ static void P_ClearSingleMapHeaderInfo(INT16 i)
 	DEH_WriteUndoline("LEVELFLAGS", va("%d", mapheaderinfo[num]->levelflags), UNDO_NONE);
 	mapheaderinfo[num]->levelflags = 0;
 	DEH_WriteUndoline("MENUFLAGS", va("%d", mapheaderinfo[num]->menuflags), UNDO_NONE);
-	mapheaderinfo[num]->menuflags = 0;
+	mapheaderinfo[num]->menuflags = (mainwads ? 0 : LF2_EXISTSHACK); // see p_setup.c - prevents replacing maps in addons with easier versions
 	// TODO grades support for delfile (pfft yeah right)
 	P_DeleteGrades(num);
 	// SRB2Kart
@@ -1120,7 +1120,7 @@ static inline void P_SpawnEmblems(void)
 static void P_SpawnSecretItems(boolean loademblems)
 {
 	// Now let's spawn those funky emblem things! Tails 12-08-2002
-	if (netgame || multiplayer || (modifiedgame && !savemoddata)) // No cheating!!
+	if (netgame || multiplayer || majormods) // No cheating!!
 		return;
 
 	if (loademblems)
@@ -3272,7 +3272,7 @@ boolean P_SetupLevel(boolean skipprecip)
 	nextmapoverride = 0;
 	skipstats = false;
 
-	if (!(netgame || multiplayer) && (!modifiedgame || savemoddata))
+	if (!(netgame || multiplayer) && !majormods)
 		mapvisited[gamemap-1] |= MV_VISITED;
 
 	levelloading = false;
@@ -3455,6 +3455,14 @@ boolean P_AddWadFile(const char *wadfilename)
 				continue;
 			num = (INT16)M_MapNumber(name[3], name[4]);
 
+			// we want to record whether this map exists. if it doesn't have a header, we can assume it's not relephant
+			if (num <= NUMMAPS && mapheaderinfo[num-1])
+			{
+				if (mapheaderinfo[num-1]->menuflags & LF2_EXISTSHACK)
+					G_SetGameModified(multiplayer, true); // oops, double-defined - no record attack privileges for you
+				mapheaderinfo[num-1]->menuflags |= LF2_EXISTSHACK;
+			}
+
 			//If you replaced the map you're on, end the level when done.
 			if (num == gamemap)
 				replacedcurrentmap = true;
@@ -3481,6 +3489,8 @@ boolean P_AddWadFile(const char *wadfilename)
 			SendNetXCmd(XD_EXITLEVEL, NULL, 0);
 	}
 
+	refreshdirmenu &= ~REFRESHDIR_GAMEDATA; // Under usual circumstances we'd wait for REFRESHDIR_GAMEDATA to disappear the next frame, but it's a bit too dangerous for that...
+
 	return true;
 }
 
diff --git a/src/p_spec.c b/src/p_spec.c
index ca4967ce..24f56c43 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -1758,12 +1758,12 @@ boolean P_RunTriggerLinedef(line_t *triggerline, mobj_t *actor, sector_t *caller
 
 	switch (specialtype)
 	{
-		case 305: // continuous
+		/*case 305: // continuous
 		case 306: // each time
 		case 307: // once
 			if (!(actor && actor->player && actor->player->charability == dist/10))
 				return false;
-			break;
+			break;*/
 		case 309: // continuous
 		case 310: // each time
 			// Only red team members can activate this.
@@ -3864,14 +3864,6 @@ DoneSection2:
 
 				P_InstaThrust(player->mo, player->mo->angle, linespeed);
 
-				/*if (GETSECSPECIAL(sector->special, 3) == 6 && (player->charability2 == CA2_SPINDASH)) // SRB2kart
-				{
-					if (!(player->pflags & PF_SPINNING))
-						player->pflags |= PF_SPINNING;
-
-					//P_SetPlayerMobjState(player->mo, S_PLAY_ATK1);
-				}*/
-
 				player->kartstuff[k_dashpadcooldown] = TICRATE/3;
 				player->kartstuff[k_drift] = 0;
 				player->kartstuff[k_driftcharge] = 0;
@@ -5781,7 +5773,7 @@ void P_SpawnSpecials(INT32 fromnetsave)
 				lines[i].special = 0;
 				continue;
 			}
-			/*else -- commented out because irrelevant to kart
+			/*else -- commented out because irrelevant to kart. keeping here because we can use these flags for something else now
 			{
 				if ((players[consoleplayer].charability == CA_THOK && (lines[i].flags & ML_NOSONIC))
 				|| (players[consoleplayer].charability == CA_FLY && (lines[i].flags & ML_NOTAILS))
@@ -7997,12 +7989,13 @@ static void P_SearchForDisableLinedefs(void)
 			}
 			else if ((lines[i].flags & ML_NETONLY) == ML_NETONLY)
 				continue; // Net-only never triggers in single player
-			else if (players[consoleplayer].charability == CA_THOK && (lines[i].flags & ML_NOSONIC))
+			// commented out because irrelevant to kart. keeping here because we can use these flags for something else now
+			/*else if (players[consoleplayer].charability == CA_THOK && (lines[i].flags & ML_NOSONIC))
 				continue;
 			else if (players[consoleplayer].charability == CA_FLY && (lines[i].flags & ML_NOTAILS))
 				continue;
 			else if (players[consoleplayer].charability == CA_GLIDEANDCLIMB && (lines[i].flags & ML_NOKNUX))
-				continue;
+				continue;*/
 
 			// Disable any linedef specials with our tag.
 			for (j = -1; (j = P_FindLineFromLineTag(&lines[i], j)) >= 0;)
diff --git a/src/p_user.c b/src/p_user.c
index d7423d80..ce411d2d 100644
--- a/src/p_user.c
+++ b/src/p_user.c
@@ -7323,74 +7323,6 @@ static void P_MovePlayer(player_t *player)
 	if (CheckForBustableBlocks)
 		P_CheckBustableBlocks(player);
 
-	// Special handling for
-	// gliding in 2D mode
-	if ((twodlevel || player->mo->flags2 & MF2_TWOD) && player->pflags & PF_GLIDING && player->charability == CA_GLIDEANDCLIMB
-		&& !(player->mo->flags & MF_NOCLIP))
-	{
-		msecnode_t *node; // only place it's being used in P_MovePlayer now
-		fixed_t oldx;
-		fixed_t oldy;
-		fixed_t floorz, ceilingz;
-
-		oldx = player->mo->x;
-		oldy = player->mo->y;
-
-		P_UnsetThingPosition(player->mo);
-		player->mo->x += player->mo->momx;
-		player->mo->y += player->mo->momy;
-		P_SetThingPosition(player->mo);
-
-		for (node = player->mo->touching_sectorlist; node; node = node->m_sectorlist_next)
-		{
-			if (!node->m_sector)
-				break;
-
-			if (node->m_sector->ffloors)
-			{
-				ffloor_t *rover;
-				fixed_t topheight, bottomheight;
-
-				for (rover = node->m_sector->ffloors; rover; rover = rover->next)
-				{
-					if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER))
-						continue;
-
-					topheight = P_GetFOFTopZ(player->mo, node->m_sector, rover, player->mo->x, player->mo->y, NULL);
-					bottomheight = P_GetFOFBottomZ(player->mo, node->m_sector, rover, player->mo->x, player->mo->y, NULL);
-					if (topheight > player->mo->z && bottomheight < player->mo->z)
-					{
-						P_ResetPlayer(player);
-						S_StartSound(player->mo, sfx_s3k4a);
-						player->climbing = 5;
-						player->mo->momx = player->mo->momy = player->mo->momz = 0;
-						break;
-					}
-				}
-			}
-
-			floorz = P_GetFloorZ(player->mo, node->m_sector, player->mo->x, player->mo->y, NULL);
-			ceilingz = P_GetCeilingZ(player->mo, node->m_sector, player->mo->x, player->mo->y, NULL);
-
-			if (player->mo->z+player->mo->height > ceilingz
-				&& node->m_sector->ceilingpic == skyflatnum)
-				continue;
-
-			if (floorz > player->mo->z || ceilingz < player->mo->z)
-			{
-				P_ResetPlayer(player);
-				S_StartSound(player->mo, sfx_s3k4a);
-				player->climbing = 5;
-				player->mo->momx = player->mo->momy = player->mo->momz = 0;
-				break;
-			}
-		}
-		P_UnsetThingPosition(player->mo);
-		player->mo->x = oldx;
-		player->mo->y = oldy;
-		P_SetThingPosition(player->mo);
-	}
-
 	// Check for a BOUNCY sector!
 	if (CheckForBouncySector)
 		P_CheckBouncySectors(player);
diff --git a/src/r_things.c b/src/r_things.c
index d6234d4b..135ae6a2 100644
--- a/src/r_things.c
+++ b/src/r_things.c
@@ -2635,7 +2635,7 @@ INT32 R_SkinAvailable(const char *name)
 }
 
 // network code calls this when a 'skin change' is received
-void SetPlayerSkin(INT32 playernum, const char *skinname)
+boolean SetPlayerSkin(INT32 playernum, const char *skinname)
 {
 	INT32 i;
 	player_t *player = &players[playernum];
@@ -2646,7 +2646,7 @@ void SetPlayerSkin(INT32 playernum, const char *skinname)
 		if (stricmp(skins[i].name, skinname) == 0)
 		{
 			SetPlayerSkinByNum(playernum, i);
-			return;
+			return true;
 		}
 	}
 
@@ -2656,6 +2656,7 @@ void SetPlayerSkin(INT32 playernum, const char *skinname)
 		CONS_Alert(CONS_WARNING, M_GetText("Player %d (%s) skin '%s' not found\n"), playernum, player_names[playernum], skinname);
 
 	SetPlayerSkinByNum(playernum, 0);
+	return false;
 }
 
 // Same as SetPlayerSkin, but uses the skin #.
@@ -2894,27 +2895,27 @@ void R_AddSkins(UINT16 wadnum)
 #define FULLPROCESS(field) else if (!stricmp(stoken, #field)) skin->field = get_number(value);
 			// character type identification
 			FULLPROCESS(flags)
-			FULLPROCESS(ability)
-			FULLPROCESS(ability2)
+			//FULLPROCESS(ability)
+			//FULLPROCESS(ability2)
 
-			FULLPROCESS(thokitem)
-			FULLPROCESS(spinitem)
-			FULLPROCESS(revitem)
+			//FULLPROCESS(thokitem)
+			//FULLPROCESS(spinitem)
+			//FULLPROCESS(revitem)
 #undef FULLPROCESS
 
 #define GETSPEED(field) else if (!stricmp(stoken, #field)) skin->field = atoi(value)<<FRACBITS;
-			GETSPEED(normalspeed)
+			//GETSPEED(normalspeed)
 			GETSPEED(runspeed)
-			GETSPEED(mindash)
-			GETSPEED(maxdash)
-			GETSPEED(actionspd)
+			//GETSPEED(mindash)
+			//GETSPEED(maxdash)
+			//GETSPEED(actionspd)
 #undef GETSPEED
 
-#define GETINT(field) else if (!stricmp(stoken, #field)) skin->field = atoi(value);
+/*#define GETINT(field) else if (!stricmp(stoken, #field)) skin->field = atoi(value);
 			GETINT(thrustfactor)
 			GETINT(accelstart)
 			GETINT(acceleration)
-#undef GETINT
+#undef GETINT*/
 
 #define GETKARTSTAT(field) \
 	else if (!stricmp(stoken, #field)) \
@@ -2933,8 +2934,8 @@ void R_AddSkins(UINT16 wadnum)
 
 			else if (!stricmp(stoken, "prefcolor"))
 				skin->prefcolor = K_GetKartColorByName(value);
-			else if (!stricmp(stoken, "jumpfactor"))
-				skin->jumpfactor = FLOAT_TO_FIXED(atof(value));
+			//else if (!stricmp(stoken, "jumpfactor"))
+				//skin->jumpfactor = FLOAT_TO_FIXED(atof(value));
 			else if (!stricmp(stoken, "highresscale"))
 				skin->highresscale = FLOAT_TO_FIXED(atof(value));
 			else
@@ -3044,6 +3045,9 @@ next_token:
 			HWR_AddPlayerMD2(numskins);
 #endif
 
+		if (skin->flags & SF_RUNONWATER) // this is literally the only way a skin can be a major mod... this might be a bit heavy handed
+			G_SetGameModified(multiplayer, true);
+
 		numskins++;
 	}
 	return;
diff --git a/src/r_things.h b/src/r_things.h
index 53784415..01d8fc07 100644
--- a/src/r_things.h
+++ b/src/r_things.h
@@ -194,7 +194,7 @@ typedef struct drawnode_s
 extern INT32 numskins;
 extern skin_t skins[MAXSKINS];
 
-void SetPlayerSkin(INT32 playernum,const char *skinname);
+boolean SetPlayerSkin(INT32 playernum,const char *skinname);
 void SetPlayerSkinByNum(INT32 playernum,INT32 skinnum); // Tails 03-16-2002
 INT32 R_SkinAvailable(const char *name);
 void R_AddSkins(UINT16 wadnum);
diff --git a/src/w_wad.c b/src/w_wad.c
index 63bee97d..efa09ce4 100644
--- a/src/w_wad.c
+++ b/src/w_wad.c
@@ -34,6 +34,7 @@
 #include "z_zone.h"
 #include "fastcmp.h"
 
+#include "g_game.h" // G_LoadGameData
 #include "filesrch.h"
 
 #include "i_video.h" // rendermode
@@ -799,6 +800,10 @@ UINT16 W_InitFile(const char *filename)
 		break;
 	}
 
+	if (refreshdirmenu & REFRESHDIR_GAMEDATA)
+		G_LoadGameData();
+	DEH_UpdateMaxFreeslots();
+
 	W_InvalidateLumpnumCache();
 	return wadfile->numlumps;
 }
diff --git a/src/y_inter.c b/src/y_inter.c
index a8b1f740..6fe71bdc 100644
--- a/src/y_inter.c
+++ b/src/y_inter.c
@@ -782,7 +782,7 @@ void Y_StartIntermission(void)
 		}
 		case int_race: // (time-only race)
 		{
-			if ((!modifiedgame || savemoddata) && !multiplayer && !demoplayback) // remove this once we have a proper time attack screen
+			if (!majormods && !multiplayer && !demoplayback) // remove this once we have a proper time attack screen
 			{
 				// Update visitation flags
 				mapvisited[gamemap-1] |= MV_BEATEN;