Index: game/engines/default/engine/Target.lua
===================================================================
--- game/engines/default/engine/Target.lua	(revision 3825)
+++ game/engines/default/engine/Target.lua	(working copy)
@@ -32,13 +32,16 @@
 
 	self.cursor = engine.Tiles:loadImage("target_cursor.png"):glTexture()
 
-	self.sr = core.display.newSurface(map.tile_w, map.tile_h)
+	--Use power of two (pot) width and height, rounded up
+	local pot_width = math.pow(2, math.ceil(math.log(map.tile_w-0.1) / math.log(2.0)))
+	local pot_height = math.pow(2, math.ceil(math.log(map.tile_h-0.1) / math.log(2.0)))
+	self.sr = core.display.newSurface(pot_width, pot_height)
 	self.sr:erase(255, 0, 0, 90)
 	self.sr = self.sr:glTexture()
-	self.sb = core.display.newSurface(map.tile_w, map.tile_h)
+	self.sb = core.display.newSurface(pot_width, pot_height)
 	self.sb:erase(0, 0, 255, 90)
 	self.sb = self.sb:glTexture()
-	self.sg = core.display.newSurface(map.tile_w, map.tile_h)
+	self.sg = core.display.newSurface(pot_width, pot_height)
 	self.sg:erase(0, 255, 0, 90)
 	self.sg = self.sg:glTexture()
 
Index: game/modules/tome/dialogs/GraphicMode.lua
===================================================================
--- game/modules/tome/dialogs/GraphicMode.lua	(revision 3825)
+++ game/modules/tome/dialogs/GraphicMode.lua	(working copy)
@@ -91,7 +91,7 @@
 	elseif self.cur_sel == "size" then
 		list = {
 			{name="64x64", sub="size", val="64x64"},
---			{name="48x48", sub="size", val="48x48"},
+			{name="48x48", sub="size", val="48x48"},
 			{name="32x32", sub="size", val="32x32"},
 			{name="16x16", sub="size", val="16x16"},
 		}
Index: game/modules/tome/class/Game.lua
===================================================================
--- game/modules/tome/class/Game.lua	(revision 3825)
+++ game/modules/tome/class/Game.lua	(working copy)
@@ -382,7 +382,7 @@
 		print("[DISPLAY MODE] Tileset: "..gfx.tiles)
 		print("[DISPLAY MODE] Size: "..gfx.size)
 
-		local do_bg = true
+		local do_bg = gfx.tiles == "ascii_full"
 		if gfx.size == "64x64" then
 			Map:setViewPort(216, 0, self.w - 216, (self.map_h_stop or 80) - 16, 64, 64, nil, 44, do_bg)
 		elseif gfx.size == "48x48" then