While my wife was spending the whole Saturday reading Harry Potter, I was spending the whole Saturday trying to get acceleration working on XP10. I leave it as an exercise for the reader to determine which of us is the bigger geek. In any case, it works now. DRM changes are pushed to xgi-0-0-2 branch and DDX changes are pushed to HEAD.
Next week I get to see if it works on 64-bit if it's still broken. I've changed so many of the internal types to the "correct" things that I suspect it might Just Work. I think I hear Nelson laughing at me somewhere...