So I tried ME2 again with 9.1. The MouseWarpOverride seems to help with the tracking issue, but everything else is the same (or worse) as in 9.0.
DLC still installs OK, but crashes when it tries to delete the rar fail. No big deal. However, loading as become a serious problem. Switching between areas now has a 50-50 chance of causing the game to go to a black screen. There is still some ambient audio and usually you can still see the mouse, but nothing else and trying to move or fire doesn't make any sound. Which means force quitting the game and starting it up again. Thankfully, it looks like the auto-save runs before that so you don't lose any progress. Still annoying though.