[flexcomponents] Skinned TileList Scrollbar shifts on click

[bryanpoopbartow]

I'm using the <mx:Style> tag to define skins for a vertical scrollbar.
 The skins look just as they should.  However, after clicking on
either one of the arrows or thumb, the whole scrollbar shifts to the
right one or two pixels.  The skins are symbols contained in a SWF.  I
have defined bounding boxes for each skin in the SWF.  I should also
mention that my skins are the same width (15 pixels) as the default
scrollbar component.  This behavior is not exhibited in the default
scrollbar, however.  Has anyone encountered this issue before or have
any ideas what I might be missing that could be causing this?  I'm
pasting my <Style> tag below, in case it helps.

<mx:Style>
             .RTOTileListVScrollBar 
             {
                upArrowUpSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='upArrowUp');
                upArrowOverSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='upArrowOver');
                upArrowDownSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='upArrowDown');
                thumbUpSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='thumbUp');
                thumbOverSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='thumbOver');
                thumbDownSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='thumbDown');
                downArrowUpSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='downArrowUp');
                downArrowOverSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='downArrowOver');
                downArrowDownSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf',
symbol='downArrowDown');
                trackSkin:
Embed(source='/bin/interface/RTOTileListVScrollBar.swf', symbol='track');
             }
        </mx:Style>