if we're centering the menu, let's center the bitmaptext objects. also, xml -> lua

stepmania/Themes/default/Graphics/ScreenTitleMenu scroll.lua

@@ -0,0 +1,11 @@
+local children = {
+	LoadFont("", "blaster") ..{
+		Text=THEME:GetString( 'ScreenTitleMenu', ThisGameCommand:GetText() );
+		InitCommand=cmd(horizalign,center;shadowlength,0);
+		GainFocusCommand=cmd(stoptweening;diffuseshift;effectperiod,0.5;effectcolor1,0.5,1,0.5,1;effectcolor2,0.25,0.5,0.25,1;);
+		LoseFocusCommand=cmd(stoptweening;stopeffect);
+		DisabledCommand=cmd(diffuse,0.5,0.5,0.5,1);
+	};
+};
+
+return Def.ActorFrame { children = children };

stepmania/Themes/default/metrics.ini

@@ -101,7 +101,7 @@ PerChoiceScrollElement=false
 ScrollerTransform=function(self,offset,itemIndex,numItems) self:y(22*offset) end
 ScrollerSecondsPerItem=0
 ScrollerNumItemsToDraw=20
-ScrollerX=SCREEN_CENTER_X-100
+ScrollerX=SCREEN_CENTER_X
 ScrollerY=SCREEN_CENTER_Y+40
 ScrollerOnCommand=
 ScrollerOffCommand=