I haven't had the swipe happening to me but something else does when in-game, full screen.
Normally in win8 in the desktop mode, you move your mouse to the bottom left and the new black start menu will pop up. The same thing happens when playing fps for example and aiming far toward left and down it will also activate the menu. In
Bad Company 2 it pushes me out of full-screen into windowed mode. I can still play fine in window mode and the menu activation doesn't happen then.
Moving the mouse left and down in Deus Ex: HR doesn't drop me out of the game or pops to window mode but simply causes the start menu to pop up over the game and disappears.
The games themselves run great on this win8 build which I was very impressed with to see.
I'm pretty sure these issues will get solved but just posting my experience feedback here for the devs.