~Johnny, on 15 September 2011 - 17:22, said:
It's rendered by DWM as 5 or 6 different layers (from what I heard at build, using the same techniques they use to render the different layers of Aero), so it takes slightly more than to just replace right now
I assume the other colors are in the DirectUI files and are linked to another resource (DWM, MSStyles, etc). If it is it's possible to change its attribute to a local resource. If that doesn't work, it's possible to create an element in between the background and the content and give that element a background attribute and make it a local resource as well.
Right now I'm getting ready to look through the DirectUI files.