We need to support the following: (at some point we do anyway) 1.Manifests, SxS, Activation Contexts etc (not just for uxtheme/comctl32 6.0 but for other stuff). This includes all the work in user32 to correctly support different activation contexts having different versions of the same window class like comctl32 6.0 does for the standard controls). 2..msstyles files. and 3.All the known uxtheme export functions (certainly those documented in MSDN and called by apps anyway) Then, all we need after that is the global hook to do non-client-area themeing
We have to implement this in the same overall way as microsoft did if we want to be compatible.