IIRC, this happens when there is a mismatch between the game and desktop resolution. It is working for me on Win764 but the game runs at a lower resolution than the desktop. Not sure how your projector rig deals with it...
Well that is probally it but not sure how to change the resolution of my desktop as I run in surround mode and I can't set custom resolution??
I was wondering what the total res should be for double screens as I remember a 2048 res limit or something because of DX7?? but 2048 by what?