diff --git a/stepmania/BackgroundEffects/Centered.xml b/stepmania/BackgroundEffects/Centered.xml
index a45bd2ead0..e09bea83a7 100644
--- a/stepmania/BackgroundEffects/Centered.xml
+++ b/stepmania/BackgroundEffects/Centered.xml
@@ -1,6 +1,6 @@
 <ActorFrame><children>
 	<AutoActor 
-		File="File1" 
+		File="Var 'File1'"
 		OnCommand="x,SCREEN_CENTER_X;y,SCREEN_CENTER_Y"
 	/>
 </children></ActorFrame>
diff --git a/stepmania/BackgroundEffects/Checkerboard1File2x2.xml b/stepmania/BackgroundEffects/Checkerboard1File2x2.xml
index 5cd523c6c3..06a21844d3 100644
--- a/stepmania/BackgroundEffects/Checkerboard1File2x2.xml
+++ b/stepmania/BackgroundEffects/Checkerboard1File2x2.xml
@@ -1,6 +1,6 @@
 <ActorFrame><children>
-	<AutoActor File="File1" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
-	<AutoActor File="File1" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
-	<AutoActor File="File1" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
-	<AutoActor File="File1" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
 </children></ActorFrame>
diff --git a/stepmania/BackgroundEffects/Checkerboard2File2x2.xml b/stepmania/BackgroundEffects/Checkerboard2File2x2.xml
index cf5166736f..9c7a813ebe 100644
--- a/stepmania/BackgroundEffects/Checkerboard2File2x2.xml
+++ b/stepmania/BackgroundEffects/Checkerboard2File2x2.xml
@@ -1,6 +1,6 @@
 <ActorFrame><children>
-	<AutoActor File="File1" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
-	<AutoActor File="File2" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
-	<AutoActor File="File2" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
-	<AutoActor File="File1" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File2'" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File2'" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
 </children></ActorFrame>
diff --git a/stepmania/BackgroundEffects/Kaleidoscope2x2.xml b/stepmania/BackgroundEffects/Kaleidoscope2x2.xml
index 7ea1a448fa..816b892e3a 100644
--- a/stepmania/BackgroundEffects/Kaleidoscope2x2.xml
+++ b/stepmania/BackgroundEffects/Kaleidoscope2x2.xml
@@ -1,6 +1,6 @@
 <ActorFrame><children>
-	<AutoActor File="File1" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
-	<AutoActor File="File1" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2;zoomx,self:GetZoomX()*-1" />
-	<AutoActor File="File1" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2;zoomy,self:GetZoomY()*-1" />
-	<AutoActor File="File1" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2;zoomx,self:GetZoomX()*-1;zoomy,self:GetZoomY()*-1" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(1,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2;zoomx,self:GetZoomX()*-1" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(1,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2;zoomy,self:GetZoomY()*-1" />
+	<AutoActor File="Var 'File1'" OnCommand="x,scale(3,0,4,SCREEN_LEFT,SCREEN_RIGHT);y,scale(3,0,4,SCREEN_TOP,SCREEN_BOTTOM);zoomtowidth,SCREEN_WIDTH/2;zoomtoheight,SCREEN_HEIGHT/2;zoomx,self:GetZoomX()*-1;zoomy,self:GetZoomY()*-1" />
 </children></ActorFrame>
diff --git a/stepmania/BackgroundEffects/SongBgWithMovieViz.xml b/stepmania/BackgroundEffects/SongBgWithMovieViz.xml
index c97a8d56b0..9c6e73dc03 100644
--- a/stepmania/BackgroundEffects/SongBgWithMovieViz.xml
+++ b/stepmania/BackgroundEffects/SongBgWithMovieViz.xml
@@ -1,12 +1,12 @@
 <ActorFrame><children>
 	<Layer
 		Type="@Sprite"
-		InitCommand="%function(self) self:LoadBackground( GAMESTATE:GetCurrentSong():GetBackgroundPath() ) self.Color = Color1 end"
+		InitCommand="%function(self) self:LoadBackground( GAMESTATE:GetCurrentSong():GetBackgroundPath() ) self.Color = Var 'Color1' end"
 		OnCommand="x,SCREEN_CENTER_X;y,SCREEN_CENTER_Y;ZoomToWidth,SCREEN_WIDTH;ZoomToHeight,SCREEN_HEIGHT;diffuse,color(self.Color)"
 	/>
 	<Layer
-		File="File1"
-		InitCommand="%function(self) self:pause(); self.Color = Color2; end"
+		File="Var 'File1'"
+		InitCommand="%function(self) self:pause(); self.Color = Var 'Color2'; end"
 		OnCommand="blend,add;x,SCREEN_CENTER_X;y,SCREEN_CENTER_Y;ZoomToWidth,SCREEN_WIDTH;ZoomToHeight,SCREEN_HEIGHT;diffuse,color(self.Color)"
 		GainFocusCommand="Play"
 		LoseFocusCommand="Pause"
diff --git a/stepmania/BackgroundEffects/StretchNoLoop.xml b/stepmania/BackgroundEffects/StretchNoLoop.xml
index 54e4e633bf..1691fd4ec8 100644
--- a/stepmania/BackgroundEffects/StretchNoLoop.xml
+++ b/stepmania/BackgroundEffects/StretchNoLoop.xml
@@ -1,6 +1,6 @@
 <ActorFrame><children>
 	<AutoActor 
-		File="File1" 
+		File="Var 'File1'" 
 		OnCommand="scale_or_crop_background;loop,0"
 	/>
 </children></ActorFrame>
diff --git a/stepmania/BackgroundEffects/StretchNormal.xml b/stepmania/BackgroundEffects/StretchNormal.xml
index 8d7c33e0bf..cba83ccb92 100644
--- a/stepmania/BackgroundEffects/StretchNormal.xml
+++ b/stepmania/BackgroundEffects/StretchNormal.xml
@@ -1,7 +1,7 @@
 <ActorFrame><children>
 	<Layer
-		File="File1" 
-		InitCommand="%function(self) self.Color = Color1; end"
+		File="Var 'File1'"
+		InitCommand="%function(self) self.Color = Var 'Color1'; end"
 		OnCommand="scale_or_crop_background;diffuse,color(self.Color)" 
 		GainFocusCommand="Play"
 		LoseFocusCommand="Pause"
diff --git a/stepmania/BackgroundEffects/StretchNormalAlignLeft.xml b/stepmania/BackgroundEffects/StretchNormalAlignLeft.xml
index a938e4e757..d2b4b6af1c 100644
--- a/stepmania/BackgroundEffects/StretchNormalAlignLeft.xml
+++ b/stepmania/BackgroundEffects/StretchNormalAlignLeft.xml
@@ -1,8 +1,8 @@
 <!-- Align left when cropping to 4:3.  Avoid this; it's not compatible with PS2 movie pre-rendering. -->
 <ActorFrame><children>
 	<Layer
-		File="File1" 
-		InitCommand="%function(self) self.Color = Color1; end"
+		File="Var 'File1'"
+		InitCommand="%function(self) self.Color = Var 'Color1'; end"
 		OnCommand="horizalign,left;scaletocover,0,0,SCREEN_WIDTH,SCREEN_HEIGHT;diffuse,color(self.Color)" 
 		GainFocusCommand="Play"
 		LoseFocusCommand="Pause"
diff --git a/stepmania/BackgroundEffects/StretchPaused.xml b/stepmania/BackgroundEffects/StretchPaused.xml
index c8fb01c9f7..96cb095ae0 100644
--- a/stepmania/BackgroundEffects/StretchPaused.xml
+++ b/stepmania/BackgroundEffects/StretchPaused.xml
@@ -1,6 +1,6 @@
 <ActorFrame><children>
 	<AutoActor 
-		File="File1" 
+		File="Var 'File1'" 
 		OnCommand="scale_or_crop_background;Pause" 
 	/>
 </children></ActorFrame>
diff --git a/stepmania/BackgroundEffects/StretchRewind.xml b/stepmania/BackgroundEffects/StretchRewind.xml
index de63c4916c..4efbc39dcd 100644
--- a/stepmania/BackgroundEffects/StretchRewind.xml
+++ b/stepmania/BackgroundEffects/StretchRewind.xml
@@ -1,6 +1,6 @@
 <ActorFrame><children>
 	<AutoActor 
-		File="File1" 
+		File="Var 'File1'" 
 		OnCommand="scale_or_crop_background;position,0"
 	/>
 </children></ActorFrame>
diff --git a/stepmania/BackgroundEffects/UpperLeft.xml b/stepmania/BackgroundEffects/UpperLeft.xml
index 8d722fd3b4..eff65f7fbd 100644
--- a/stepmania/BackgroundEffects/UpperLeft.xml
+++ b/stepmania/BackgroundEffects/UpperLeft.xml
@@ -1,4 +1,4 @@
 <ActorFrame><children>
 	<!-- upper left corner -->
-	<AutoActor File="File1" />
+	<AutoActor File="Var 'File1'" />
 </children></ActorFrame>
diff --git a/stepmania/src/Background.cpp b/stepmania/src/Background.cpp
index acb8ee91bd..388ec76965 100644
--- a/stepmania/src/Background.cpp
+++ b/stepmania/src/Background.cpp
@@ -295,12 +295,13 @@ bool BackgroundImpl::Layer::CreateBackground( const Song *pSong, const Backgroun
 
 	vector<RString> vsResolved;
 	vsResolved.resize( vsToResolve.size() );
+	vector<LuaThreadVariable *> vsResolvedRef;
+	vsResolvedRef.resize( vsToResolve.size() );
+
 	for( unsigned i=0; i<vsToResolve.size(); i++ )
 	{
 		const RString &sToResolve = vsToResolve[i];
 	
-		LUA->UnsetGlobal( ssprintf("File%d",i+1) );	// clear
-		
 		if( sToResolve.empty() )
 		{
 			if( i == 0 )
@@ -341,7 +342,7 @@ bool BackgroundImpl::Layer::CreateBackground( const Song *pSong, const Backgroun
 		
 		ASSERT( !sResolved.empty() );
 
-		LUA->SetGlobal( ssprintf("File%d",i+1), sResolved );
+		vsResolvedRef[i] = new LuaThreadVariable( ssprintf("File%d",i+1), sResolved );
 	}
 
 	RString sEffect = bd.m_sEffect;
@@ -369,8 +370,8 @@ bool BackgroundImpl::Layer::CreateBackground( const Song *pSong, const Backgroun
 
 
 	// Set Lua color globals
-	LUA->SetGlobal( "Color1", bd.m_sColor1.empty() ? RString("1,1,1,1") : bd.m_sColor1 );
-	LUA->SetGlobal( "Color2", bd.m_sColor2.empty() ? RString("1,1,1,1") : bd.m_sColor2 );
+	LuaThreadVariable sColor1( "Color1", bd.m_sColor1.empty() ? RString("1,1,1,1") : bd.m_sColor1 );
+	LuaThreadVariable sColor2( "Color2", bd.m_sColor2.empty() ? RString("1,1,1,1") : bd.m_sColor2 );
 
 
 	// Resolve the effect file.
@@ -403,10 +404,8 @@ bool BackgroundImpl::Layer::CreateBackground( const Song *pSong, const Backgroun
 	ASSERT( pActor );
 	m_BGAnimations[bd] = pActor;
 
-	for( unsigned i=0; i<vsResolved.size(); i++ )
-		LUA->UnsetGlobal( ssprintf("File%d",i+1) );
-	LUA->UnsetGlobal( "Color1" );
-	LUA->UnsetGlobal( "Color2" );
+	for( unsigned i=0; i<vsResolvedRef.size(); i++ )
+		delete vsResolvedRef[i];
 
 	return true;
 }
@@ -805,17 +804,10 @@ void BackgroundImpl::Layer::UpdateCurBGChange( const Song *pSong, float fLastMus
 
 		m_pCurrentBGA->SetUpdateRate( change.m_fRate );
 
-		// Set Lua color globals before calling Init and On
-		LUA->SetGlobal( "Color1", change.m_def.m_sColor1.empty() ? RString("1,1,1,1") : change.m_def.m_sColor1 );
-		LUA->SetGlobal( "Color2", change.m_def.m_sColor2.empty() ? RString("1,1,1,1") : change.m_def.m_sColor2 );
-		
 		m_pCurrentBGA->InitState();
 		m_pCurrentBGA->PlayCommand( "On" );
 		m_pCurrentBGA->PlayCommand( "GainFocus" );
 
-		LUA->UnsetGlobal( "Color1" );
-		LUA->UnsetGlobal( "Color2" );
-
 		/* How much time of this BGA have we skipped?  (This happens with SetSeconds.) */
 		const float fStartSecond = pSong->m_Timing.GetElapsedTimeFromBeat( change.m_fStartBeat );
 
diff --git a/stepmania/src/ScreenManager.cpp b/stepmania/src/ScreenManager.cpp
index 7d4ec21fa3..f957ea0c10 100644
--- a/stepmania/src/ScreenManager.cpp
+++ b/stepmania/src/ScreenManager.cpp
@@ -124,9 +124,10 @@ namespace ScreenManagerUtil
 		g_ScreenStack.push_back( ls );
 
 		/* Set the name of the loading screen. */
-		LUA->SetGlobal( "LoadingScreen", ls.m_pScreen->GetName() );
-		ls.m_pScreen->BeginScreen();
-		LUA->UnsetGlobal( "LoadingScreen" );
+		{
+			LuaThreadVariable var( "LoadingScreen", ls.m_pScreen->GetName() );
+			ls.m_pScreen->BeginScreen();
+		}
 
 		SCREENMAN->RefreshCreditsMessages();