diff --git a/src/doomdef.h b/src/doomdef.h
index 9c8197e07..e28206b08 100644
--- a/src/doomdef.h
+++ b/src/doomdef.h
@@ -338,6 +338,7 @@ enum : unsigned int
 	COMPATF2_EXPLODE1		= 1 << 8,	// No vertical explosion thrust
 	COMPATF2_EXPLODE2		= 1 << 9,	// Use original explosion code throughout.
 	COMPATF2_RAILING		= 1 << 10,	// Bugged Strife railings.
+	COMPATF2_SCRIPTWAIT		= 1 << 11,	// Use old scriptwait implementation where it doesn't wait on a non-running script.
 };
 
 // Emulate old bugs for select maps. These are not exposed by a cvar
@@ -353,7 +354,7 @@ enum
 	BCOMPATF_LINKFROZENPROPS	= 1 << 6,	// Clearing PROP_TOTALLYFROZEN or PROP_FROZEN also clears the other
 	BCOMPATF_FLOATBOB			= 1 << 8,	// Use Hexen's original method of preventing floatbobbing items from falling down
 	BCOMPATF_NOSLOPEID			= 1 << 9,	// disable line IDs on slopes.
-	BCOMPATF_CLIPMIDTEX		= 1 << 10,	// Always Clip midtex's in the software renderer (required to run certain GZDoom maps)
+	BCOMPATF_CLIPMIDTEX			= 1 << 10,	// Always Clip midtex's in the software renderer (required to run certain GZDoom maps, has no effect in the hardware renderer)
 };
 
 // phares 3/20/98:
diff --git a/src/gamedata/g_mapinfo.cpp b/src/gamedata/g_mapinfo.cpp
index bb6138687..f4c059105 100644
--- a/src/gamedata/g_mapinfo.cpp
+++ b/src/gamedata/g_mapinfo.cpp
@@ -1685,6 +1685,7 @@ MapFlagHandlers[] =
 	{ "compat_explode1",				MITYPE_COMPATFLAG, 0, COMPATF2_EXPLODE1 },
 	{ "compat_explode2",				MITYPE_COMPATFLAG, 0, COMPATF2_EXPLODE2 },
 	{ "compat_railing",					MITYPE_COMPATFLAG, 0, COMPATF2_RAILING },
+	{ "compat_scriptwait",				MITYPE_COMPATFLAG, 0, COMPATF2_SCRIPTWAIT },
 	{ "cd_start_track",					MITYPE_EATNEXT,	0, 0 },
 	{ "cd_end1_track",					MITYPE_EATNEXT,	0, 0 },
 	{ "cd_end2_track",					MITYPE_EATNEXT,	0, 0 },
diff --git a/src/maploader/compatibility.cpp b/src/maploader/compatibility.cpp
index bf9d389c7..5b23b51be 100644
--- a/src/maploader/compatibility.cpp
+++ b/src/maploader/compatibility.cpp
@@ -169,6 +169,7 @@ static FCompatOption Options[] =
 	{ "explode1",				COMPATF2_EXPLODE1, SLOT_COMPAT2 },
 	{ "explode2",				COMPATF2_EXPLODE2, SLOT_COMPAT2 },
 	{ "railing",				COMPATF2_RAILING, SLOT_COMPAT2 },
+	{ "scriptwait",				COMPATF2_SCRIPTWAIT, SLOT_COMPAT2 },
 	{ NULL, 0, 0 }
 };
 
diff --git a/src/playsim/p_acs.cpp b/src/playsim/p_acs.cpp
index 0cb77f19e..46cb8191e 100644
--- a/src/playsim/p_acs.cpp
+++ b/src/playsim/p_acs.cpp
@@ -8308,9 +8308,21 @@ scriptwait:
 			break;
 
 		case PCD_SCRIPTWAITDIRECT:
-			statedata = uallong(pc[0]);
-			pc++;
-			goto scriptwait;
+			if (!(Level->i_compatflags2 & COMPATF2_SCRIPTWAIT))
+			{
+				statedata = uallong(pc[0]);
+				pc++;
+				goto scriptwait;
+			}
+			else
+			{
+				// Old implementation for compatibility with Daedalus MAP19
+				state = SCRIPT_ScriptWait;
+				statedata = uallong(pc[0]);
+				pc++;
+				PutLast();
+				break;
+			}
 
 		case PCD_SCRIPTWAITNAMED:
 			statedata = -FName(Level->Behaviors.LookupString(STACK(1)));
diff --git a/wadsrc/static/compatibility.txt b/wadsrc/static/compatibility.txt
index 1c2c4104b..e534146ef 100644
--- a/wadsrc/static/compatibility.txt
+++ b/wadsrc/static/compatibility.txt
@@ -287,3 +287,8 @@ DC96228097DD004C40CCB1DB14A91EAA // unloved.pk3:unlovedmaps.wad map05
 	clipmidtex
 	checkswitchrange
 }
+
+F50C91A05E1A1E646690517641F0D1DD // daedalus.wad map19
+{
+	scriptwait
+}