diff --git a/src/d_clisrv.c b/src/d_clisrv.c
index 7d0e44b45..36d13fc14 100644
--- a/src/d_clisrv.c
+++ b/src/d_clisrv.c
@@ -2244,7 +2244,7 @@ static void Command_connect(void)
 	// Assume we connect directly.
 	boolean viams = false;
 
-	if (COM_Argc() < 2)
+	if (COM_Argc() < 2 || *COM_Argv(1) == 0)
 	{
 		CONS_Printf(M_GetText(
 			"Connect <serveraddress> (port): connect to a server\n"
diff --git a/src/d_main.c b/src/d_main.c
index 063d28453..fbec5f7d8 100644
--- a/src/d_main.c
+++ b/src/d_main.c
@@ -730,11 +730,6 @@ void D_StartTitle(void)
 	CON_ToggleOff();
 
 	// Reset the palette
-#ifdef HWRENDER
-	if (rendermode == render_opengl)
-		HWR_SetPaletteColor(0);
-	else
-#endif
 	if (rendermode != render_none)
 		V_SetPaletteLump("PLAYPAL");
 }
@@ -1068,7 +1063,7 @@ void D_SRB2Main(void)
 
 	// add any files specified on the command line with -file wadfile
 	// to the wad list
-	if (!(M_CheckParm("-connect")))
+	if (!(M_CheckParm("-connect") && !M_CheckParm("-server")))
 	{
 		if (M_CheckParm("-file"))
 		{
@@ -1224,7 +1219,15 @@ void D_SRB2Main(void)
 	R_Init();
 
 	// setting up sound
-	CONS_Printf("S_Init(): Setting up sound.\n");
+	if (dedicated)
+	{
+		nosound = true;
+		nomidimusic = nodigimusic = true;
+	}
+	else
+	{
+		CONS_Printf("S_Init(): Setting up sound.\n");
+	}
 	if (M_CheckParm("-nosound"))
 		nosound = true;
 	if (M_CheckParm("-nomusic")) // combines -nomidimusic and -nodigmusic
@@ -1323,7 +1326,7 @@ void D_SRB2Main(void)
 		ultimatemode = true;
 	}
 
-	if (autostart || netgame || M_CheckParm("+connect") || M_CheckParm("-connect"))
+	if (autostart || netgame)
 	{
 		gameaction = ga_nothing;
 
@@ -1361,8 +1364,7 @@ void D_SRB2Main(void)
 			}
 		}
 
-		if (server && !M_CheckParm("+map") && !M_CheckParm("+connect")
-			&& !M_CheckParm("-connect"))
+		if (server && !M_CheckParm("+map"))
 		{
 			// Prevent warping to nonexistent levels
 			if (W_CheckNumForName(G_BuildMapName(pstartmap)) == LUMPERROR)
diff --git a/src/d_netfil.c b/src/d_netfil.c
index 172624ad2..6742cfe28 100644
--- a/src/d_netfil.c
+++ b/src/d_netfil.c
@@ -990,19 +990,41 @@ filestatus_t checkfilemd5(char *filename, const UINT8 *wantedmd5sum)
 	return FS_FOUND; // will never happen, but makes the compiler shut up
 }
 
+// Rewritten by Monster Iestyn to be less stupid
+// Note: if completepath is true, "filename" is modified, but only if FS_FOUND is going to be returned
+// (Don't worry about WinCE's version of filesearch, nobody cares about that OS anymore)
 filestatus_t findfile(char *filename, const UINT8 *wantedmd5sum, boolean completepath)
 {
-	filestatus_t homecheck = filesearch(filename, srb2home, wantedmd5sum, false, 10);
-	if (homecheck == FS_FOUND)
-		return filesearch(filename, srb2home, wantedmd5sum, completepath, 10);
+	filestatus_t homecheck; // store result of last file search
+	boolean badmd5 = false; // store whether md5 was bad from either of the first two searches (if nothing was found in the third)
 
-	homecheck = filesearch(filename, srb2path, wantedmd5sum, false, 10);
-	if (homecheck == FS_FOUND)
-		return filesearch(filename, srb2path, wantedmd5sum, completepath, 10);
+	// first, check SRB2's "home" directory
+	homecheck = filesearch(filename, srb2home, wantedmd5sum, completepath, 10);
 
+	if (homecheck == FS_FOUND) // we found the file, so return that we have :)
+		return FS_FOUND;
+	else if (homecheck == FS_MD5SUMBAD) // file has a bad md5; move on and look for a file with the right md5
+		badmd5 = true;
+	// if not found at all, just move on without doing anything
+
+	// next, check SRB2's "path" directory
+	homecheck = filesearch(filename, srb2path, wantedmd5sum, completepath, 10);
+
+	if (homecheck == FS_FOUND) // we found the file, so return that we have :)
+		return FS_FOUND;
+	else if (homecheck == FS_MD5SUMBAD) // file has a bad md5; move on and look for a file with the right md5
+		badmd5 = true;
+	// if not found at all, just move on without doing anything
+
+	// finally check "." directory
 #ifdef _arch_dreamcast
-	return filesearch(filename, "/cd", wantedmd5sum, completepath, 10);
+	homecheck = filesearch(filename, "/cd", wantedmd5sum, completepath, 10);
 #else
-	return filesearch(filename, ".", wantedmd5sum, completepath, 10);
+	homecheck = filesearch(filename, ".", wantedmd5sum, completepath, 10);
 #endif
+
+	if (homecheck != FS_NOTFOUND) // if not found this time, fall back on the below return statement
+		return homecheck; // otherwise return the result we got
+
+	return (badmd5 ? FS_MD5SUMBAD : FS_NOTFOUND); // md5 sum bad or file not found
 }
diff --git a/src/g_game.c b/src/g_game.c
index d3c55e0cc..bcae69fda 100644
--- a/src/g_game.c
+++ b/src/g_game.c
@@ -3588,7 +3588,8 @@ void G_InitNew(UINT8 pultmode, const char *mapname, boolean resetplayer, boolean
 		unlocktriggers = 0;
 
 		// clear itemfinder, just in case
-		CV_StealthSetValue(&cv_itemfinder, 0);
+		if (!dedicated) // except in dedicated servers, where it is not registered and can actually I_Error debug builds
+			CV_StealthSetValue(&cv_itemfinder, 0);
 	}
 
 	// internal game map
diff --git a/src/hardware/hw_main.c b/src/hardware/hw_main.c
index 81021ef7f..a5fe6b673 100644
--- a/src/hardware/hw_main.c
+++ b/src/hardware/hw_main.c
@@ -2901,8 +2901,8 @@ static boolean HWR_CheckBBox(fixed_t *bspcoord)
 	py2 = bspcoord[checkcoord[boxpos][3]];
 
 	// check clip list for an open space
-	angle1 = R_PointToAngle(px1, py1) - dup_viewangle;
-	angle2 = R_PointToAngle(px2, py2) - dup_viewangle;
+	angle1 = R_PointToAngle2(dup_viewx>>1, dup_viewy>>1, px1>>1, py1>>1) - dup_viewangle;
+	angle2 = R_PointToAngle2(dup_viewx>>1, dup_viewy>>1, px2>>1, py2>>1) - dup_viewangle;
 
 	span = angle1 - angle2;
 
@@ -4228,6 +4228,9 @@ static void HWR_SplitSprite(gr_vissprite_t *spr)
 	i = 0;
 	temp = FLOAT_TO_FIXED(realtop);
 
+	if (spr->mobj->frame & FF_FULLBRIGHT)
+		lightlevel = 255;
+
 #ifdef ESLOPE
 	for (i = 1; i < sector->numlights; i++)
 	{
@@ -4235,14 +4238,16 @@ static void HWR_SplitSprite(gr_vissprite_t *spr)
 					: sector->lightlist[i].height;
 		if (h <= temp)
 		{
-			lightlevel = *list[i-1].lightlevel;
+			if (!(spr->mobj->frame & FF_FULLBRIGHT))
+				lightlevel = *list[i-1].lightlevel;
 			colormap = list[i-1].extra_colormap;
 			break;
 		}
 	}
 #else
 	i = R_GetPlaneLight(sector, temp, false);
-	lightlevel = *list[i].lightlevel;
+	if (!(spr->mobj->frame & FF_FULLBRIGHT))
+		lightlevel = *list[i].lightlevel;
 	colormap = list[i].extra_colormap;
 #endif
 
@@ -4257,7 +4262,8 @@ static void HWR_SplitSprite(gr_vissprite_t *spr)
 		// even if we aren't changing colormap or lightlevel, we still need to continue drawing down the sprite
 		if (!(list[i].flags & FF_NOSHADE) && (list[i].flags & FF_CUTSPRITES))
 		{
-			lightlevel = *list[i].lightlevel;
+			if (!(spr->mobj->frame & FF_FULLBRIGHT))
+				lightlevel = *list[i].lightlevel;
 			colormap = list[i].extra_colormap;
 		}
 
diff --git a/src/m_fixed.c b/src/m_fixed.c
index ce7471a28..014457386 100644
--- a/src/m_fixed.c
+++ b/src/m_fixed.c
@@ -33,7 +33,9 @@
 */
 fixed_t FixedMul(fixed_t a, fixed_t b)
 {
-	return (fixed_t)((((INT64)a * b) ) / FRACUNIT);
+	// Need to cast to unsigned before shifting to avoid undefined behaviour
+	// for negative integers
+	return (fixed_t)(((UINT64)((INT64)a * b)) >> FRACBITS);
 }
 
 #endif //__USE_C_FIXEDMUL__
diff --git a/src/m_menu.c b/src/m_menu.c
index ea93d1e2d..79ac6800b 100644
--- a/src/m_menu.c
+++ b/src/m_menu.c
@@ -6295,6 +6295,13 @@ static void M_DrawConnectIPMenu(void)
 static void M_ConnectIP(INT32 choice)
 {
 	(void)choice;
+
+	if (*setupm_ip == 0)
+	{
+		M_StartMessage("You must specify an IP address.\n", NULL, MM_NOTHING);
+		return;
+	}
+
 	COM_BufAddText(va("connect \"%s\"\n", setupm_ip));
 
 	// A little "please wait" message.
@@ -6536,7 +6543,7 @@ static void M_HandleSetupMultiPlayer(INT32 choice)
 			if (choice < 32 || choice > 127 || itemOn != 0)
 				break;
 			l = strlen(setupm_name);
-			if (l < MAXPLAYERNAME-1)
+			if (l < MAXPLAYERNAME)
 			{
 				S_StartSound(NULL,sfx_menu1); // Tails
 				setupm_name[l] =(char)choice;
diff --git a/src/p_setup.c b/src/p_setup.c
index 8e746457b..d8c913e0f 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -2503,11 +2503,6 @@ boolean P_SetupLevel(boolean skipprecip)
 
 
 	// Reset the palette
-#ifdef HWRENDER
-	if (rendermode == render_opengl)
-		HWR_SetPaletteColor(0);
-	else
-#endif
 	if (rendermode != render_none)
 		V_SetPaletteLump("PLAYPAL");
 
@@ -2565,6 +2560,7 @@ boolean P_SetupLevel(boolean skipprecip)
 	{
 		tic_t starttime = I_GetTime();
 		tic_t endtime = starttime + (3*TICRATE)/2;
+		tic_t nowtime;
 
 		S_StartSound(NULL, sfx_s3kaf);
 
@@ -2574,9 +2570,17 @@ boolean P_SetupLevel(boolean skipprecip)
 		F_WipeEndScreen();
 		F_RunWipe(wipedefs[wipe_speclevel_towhite], false);
 
+		nowtime = lastwipetic;
 		// Hold on white for extra effect.
-		while (I_GetTime() < endtime)
-			I_Sleep();
+		while (nowtime < endtime)
+		{
+			// wait loop
+			while (!((nowtime = I_GetTime()) - lastwipetic))
+				I_Sleep();
+			lastwipetic = nowtime;
+			if (moviemode) // make sure we save frames for the white hold too
+				M_SaveFrame();
+		}
 
 		ranspecialwipe = 1;
 	}
@@ -2994,7 +2998,7 @@ boolean P_AddWadFile(const char *wadfilename, char **firstmapname)
 
 	if ((numlumps = W_LoadWadFile(wadfilename)) == INT16_MAX)
 	{
-		CONS_Printf(M_GetText("Errors occured while loading %s; not added.\n"), wadfilename);
+		CONS_Printf(M_GetText("Errors occurred while loading %s; not added.\n"), wadfilename);
 		return false;
 	}
 	else wadnum = (UINT16)(numwadfiles-1);
diff --git a/src/sdl/i_video.c b/src/sdl/i_video.c
index 87ce84158..4eab0ae3c 100644
--- a/src/sdl/i_video.c
+++ b/src/sdl/i_video.c
@@ -658,6 +658,14 @@ static void Impl_HandleMouseButtonEvent(SDL_MouseButtonEvent evt, Uint32 type)
 
 	SDL_memset(&event, 0, sizeof(event_t));
 
+	// Ignore the event if the mouse is not actually focused on the window.
+	// This can happen if you used the mouse to restore keyboard focus;
+	// this apparently makes a mouse button down event but not a mouse button up event,
+	// resulting in whatever key was pressed down getting "stuck" if we don't ignore it.
+	// -- Monster Iestyn (28/05/18)
+	if (SDL_GetMouseFocus() != window)
+		return;
+
 	/// \todo inputEvent.button.which
 	if (USE_MOUSEINPUT)
 	{
diff --git a/src/sdl/sdl_sound.c b/src/sdl/sdl_sound.c
index 1a2cabd23..6c70c163b 100644
--- a/src/sdl/sdl_sound.c
+++ b/src/sdl/sdl_sound.c
@@ -1180,12 +1180,6 @@ void I_StartupSound(void)
 	audio.callback = I_UpdateStream;
 	audio.userdata = &localdata;
 
-	if (dedicated)
-	{
-		nosound = nomidimusic = nodigimusic = true;
-		return;
-	}
-
 	// Configure sound device
 	CONS_Printf("I_StartupSound:\n");
 
@@ -1481,9 +1475,6 @@ void I_InitMusic(void)
 	I_AddExitFunc(I_ShutdownGMEMusic);
 #endif
 
-	if ((nomidimusic && nodigimusic) || dedicated)
-		return;
-
 #ifdef HAVE_MIXER
 	MIX_VERSION(&MIXcompiled)
 	MIXlinked = Mix_Linked_Version();
diff --git a/src/st_stuff.c b/src/st_stuff.c
index 3562a9b71..72e0b6b94 100644
--- a/src/st_stuff.c
+++ b/src/st_stuff.c
@@ -210,17 +210,17 @@ void ST_doPaletteStuff(void)
 	else
 		palette = 0;
 
+#ifdef HWRENDER
+	if (rendermode == render_opengl)
+		palette = 0; // No flashpals here in OpenGL
+#endif
+
 	palette = min(max(palette, 0), 13);
 
 	if (palette != st_palette)
 	{
 		st_palette = palette;
 
-#ifdef HWRENDER
-		if (rendermode == render_opengl)
-			HWR_SetPaletteColor(0);
-		else
-#endif
 		if (rendermode != render_none)
 		{
 			V_SetPaletteLump(GetPalette()); // Reset the palette