Quote Originally Posted by Freddie View Post
I think I know what's wrong but I haven't figured out what to do about it.

I think it's just that when you Alt Tab, by the time you release the Alt key, WoW is no longer the focus window, so Mojo never broadcasts the release of the Alt key.

As a result, Mojo's key state tables (the fake ones it maintains for each WoW) show the Alt key down. Then next time you broadcast a key, Mojo translates the key with the screwed up key state tables. This could have odd effects since the operating system has a complicated way of interpreting keystrokes when Alt is down.
What about marking all keys as released (and sending the relevant key up events) when the focused window changes?