OK sorry let me update again, yes now it does work when go to the edge of the screen. It didn't give a message to restart the game for that to be enabled, but looks like that is all it took.
So I guess add a message that you have to restart before it takes effect.
EDIT
And yes, I do have to say it crashed again when I alt-tabbed to type this message.
I think it said, DX error: Invalid call