diff --git a/specs/usdf.txt b/specs/usdf.txt
index 52b418d46..1367ccfbf 100644
--- a/specs/usdf.txt
+++ b/specs/usdf.txt
@@ -113,14 +113,14 @@ conversation // Starts a dialog.
 
             // The amount of an item needed to successfully pick this option.
             // This can be repeated, but only the first will be shown (provided 
-            // diaplaycost is true).  All costs must be satisfied for success.
+            // displaycost is true).  All costs must be satisfied for success.
             cost
             {
                 item   = <integer>; // Item that is required for this option.
                 amount = <integer>; // Minimum amount of the item needed.
             }
 
-            displaycost     = <bool>;    // Weather the cost should be
+            displaycost     = <bool>;    // Whether the cost should be
                                          // displayed with the option.
                                          // If no cost is specified this should
                                          // be ignored.
diff --git a/src/g_doom/a_bossbrain.cpp b/src/g_doom/a_bossbrain.cpp
index 873b5c6dc..a99ef9323 100644
--- a/src/g_doom/a_bossbrain.cpp
+++ b/src/g_doom/a_bossbrain.cpp
@@ -124,12 +124,12 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_BrainSpit)
 		// spawn brain missile
 		spit = P_SpawnMissile (self, targ, spawntype);
 
-		// Boss cubes should move freely to their destination so it's
-		// probably best to disable all collision detection for them.
-
 		if (spit != NULL)
 		{
+			// Boss cubes should move freely to their destination so it's
+			// probably best to disable all collision detection for them.
 			if (spit->flags & MF_NOCLIP) spit->flags5 |= MF5_NOINTERACTION;
+	
 			spit->target = targ;
 			spit->master = self;
 			// [RH] Do this correctly for any trajectory. Doom would divide by 0
diff --git a/src/p_floor.cpp b/src/p_floor.cpp
index e9768479b..f63087619 100644
--- a/src/p_floor.cpp
+++ b/src/p_floor.cpp
@@ -283,7 +283,6 @@ bool EV_DoFloor (DFloor::EFloor floortype, line_t *line, int tag,
 	bool 		rtn;
 	sector_t*	sec;
 	DFloor*		floor;
-	//bool		manual = false; tag == 0 and manual == true constitutes the same evidence [fdari]
 	fixed_t		ceilingheight;
 	fixed_t		newheight;
 	vertex_t	*spot, *spot2;
@@ -296,7 +295,6 @@ bool EV_DoFloor (DFloor::EFloor floortype, line_t *line, int tag,
 		if (!line || !(sec = line->backsector))
 			return rtn;
 		secnum = (int)(sec-sectors);
-		//manual = true;
 		goto manual_floor;
 	}
 
@@ -814,7 +812,6 @@ bool EV_DoDonut (int tag, line_t *line, fixed_t pillarspeed, fixed_t slimespeed)
 	DFloor*				floor;
 	vertex_t*			spot;
 	fixed_t				height;
-	// bool				manual = false; Instead of breaking when manual is true, fail to (re)enter loop when tag is false (0).
 		
 	secnum = -1;
 	rtn = false;
@@ -823,7 +820,6 @@ bool EV_DoDonut (int tag, line_t *line, fixed_t pillarspeed, fixed_t slimespeed)
 	{
 		if (!line || !(s1 = line->backsector))
 			return rtn;
-		//manual = true;
 		goto manual_donut;
 	}
 
@@ -1378,7 +1374,6 @@ bool EV_StartWaggle (int tag, line_t *line, int height, int speed, int offset,
 	sector_t *sector;
 	DWaggleBase *waggle;
 	bool retCode;
-	//bool manual = false;
 
 	retCode = false;
 	sectorIndex = -1;
@@ -1387,7 +1382,6 @@ bool EV_StartWaggle (int tag, line_t *line, int height, int speed, int offset,
 	{
 		if (!line || !(sector = line->backsector))
 			return retCode;
-		//manual = true;
 		goto manual_waggle;
 	}
 
diff --git a/src/p_glnodes.cpp b/src/p_glnodes.cpp
index 694c1684b..7a14e4d44 100644
--- a/src/p_glnodes.cpp
+++ b/src/p_glnodes.cpp
@@ -1498,7 +1498,7 @@ void P_SetRenderSector()
 		seg_t *seg = ss->firstline;
 
 		// Check for one-dimensional subsectors. These should be ignored when
-		// being processed for automap drawinng etc.
+		// being processed for automap drawing etc.
 		ss->flags |= SSECF_DEGENERATE;
 		for(j=2; j<ss->numlines; j++)
 		{
diff --git a/src/r_main.cpp b/src/r_main.cpp
index f4ba8c6e5..edb13d326 100644
--- a/src/r_main.cpp
+++ b/src/r_main.cpp
@@ -263,7 +263,7 @@ void R_SetVisibility (float vis)
 
 	CurrentVisibility = vis;
 
-	if (FocalTangent == 0)
+	if (FocalTangent == 0 || FocalLengthY == 0)
 	{ // If r_visibility is called before the renderer is all set up, don't
 	  // divide by zero. This will be called again later, and the proper
 	  // values can be initialized then.