diff --git a/src/g_mapinfo.cpp b/src/g_mapinfo.cpp
index f1e55c9025..fb05bd52ba 100644
--- a/src/g_mapinfo.cpp
+++ b/src/g_mapinfo.cpp
@@ -312,8 +312,13 @@ FString level_info_t::LookupLevelName()
 			{
 				mysnprintf (checkstring, countof(checkstring), "%d: ", atoi(&MapName[5]));
 			}
+			else
+			{
+				// make sure nothing is stripped.
+				checkstring[0] = '\0';
+			}
 			thename = strstr (lookedup, checkstring);
-			if (thename == NULL)
+			if (thename == NULL || thename == lookedup)
 			{
 				thename = lookedup;
 			}
diff --git a/src/p_tags.cpp b/src/p_tags.cpp
index e773b691fc..851c4ee94d 100644
--- a/src/p_tags.cpp
+++ b/src/p_tags.cpp
@@ -309,13 +309,24 @@ int FSectorTagIterator::Next()
 		ret = start;
 		start = -1;
 	}
-	else
+	else if (searchtag != 0)
 	{
 		while (start >= 0 && tagManager.allTags[start].tag != searchtag) start = tagManager.allTags[start].nexttag;
 		if (start == -1) return -1;
 		ret = tagManager.allTags[start].target;
 		start = tagManager.allTags[start].nexttag;
 	}
+	else
+	{
+		// with the tag manager, searching for tag 0 has to be different, because it won't create entries for untagged sectors.
+		while (start < numsectors && tagManager.SectorHasTags(start))
+		{
+			start++;
+		}
+		if (start == numsectors) return -1;
+		ret = start;
+		start++;
+	}
 	return ret;
 }
 
diff --git a/src/p_tags.h b/src/p_tags.h
index 2195821c15..75d397d8d3 100644
--- a/src/p_tags.h
+++ b/src/p_tags.h
@@ -79,7 +79,7 @@ public:
 	FSectorTagIterator(int tag)
 	{
 		searchtag = tag;
-		start = tagManager.TagHashFirst[((unsigned int)tag) % FTagManager::TAG_HASH_SIZE];
+		start = tag == 0 ? 0 : tagManager.TagHashFirst[((unsigned int)tag) % FTagManager::TAG_HASH_SIZE];
 	}
 
 	// Special constructor for actions that treat tag 0 as  'back of activation line'
diff --git a/src/thingdef/thingdef_codeptr.cpp b/src/thingdef/thingdef_codeptr.cpp
index be9c06d609..941aa0a593 100644
--- a/src/thingdef/thingdef_codeptr.cpp
+++ b/src/thingdef/thingdef_codeptr.cpp
@@ -6238,8 +6238,7 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_JumpIfHigherOrLower)
 //
 // A_SetRipperLevel(int level)
 //
-// Sets the ripper level/requirement of the calling actor.
-// Also sets the minimum and maximum levels to rip through.
+// Sets the ripper level of the calling actor.
 //===========================================================================
 DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetRipperLevel)
 {
@@ -6253,8 +6252,7 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetRipperLevel)
 //
 // A_SetRipMin(int min)
 //
-// Sets the ripper level/requirement of the calling actor.
-// Also sets the minimum and maximum levels to rip through.
+// Sets the minimum level a ripper must be in order to rip through this actor.
 //===========================================================================
 DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetRipMin)
 {
@@ -6266,10 +6264,9 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetRipMin)
 
 //===========================================================================
 //
-// A_SetRipMin(int min)
+// A_SetRipMax(int max)
 //
-// Sets the ripper level/requirement of the calling actor.
-// Also sets the minimum and maximum levels to rip through.
+// Sets the minimum level a ripper must be in order to rip through this actor.
 //===========================================================================
 DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_SetRipMax)
 {