So I just downloaded Lion on my MacBook Pro. I'm using it on an external monitor, as my screen on my MacBook Pro is broken. But I restarted my Mac and I get this grey screen. But it's like there's 2 screens; 1 on my MacBook Pro and 2 on my external monitor. When I move the mouse over to the left, it disappears so it seems like the screens are split. But the only thing I can see is this totally grey screen (or this grey wallpaper they introduced in the iOS 4 multitasking bar). How does I fix this?