It may be the window text, not using wb8, not positive, if it is, it will change the bulk of your window text making the skin useless.
I know this does not help, but an empty post is discouraging. Someone with a definite answer will be along, I am sure of it.
Could be hard coded also, if so you would have to change maybe the button face /dialogue background or window background.
But, just rambling until you get real help,lol.