As I understand it, WebBlinds uses an older verison of Stardock's DirectSkin, which doesn't skin scrollbars. However, if you let WebBlinds use the current WindowBlinds skin, instead of forcing a particular skin on it, it will skin the scrollbars. You can still set the throbber and toolbar icons to whatever you want and use the pop-up blocker.
I already have coffee, but thanks for the donuts.
