Yes. Same thing happens. When I push or hold the F1 key, the game window disappears and I am back at the desktop. Then I hear the "Trainer Activated" voice. The funny part is is that there's no game running!
Crytek played this one beautifully.
I overlooked a previous post suggesting to hit the F1 key almost immediately after double-clicking the Crysis 3 icon (After starting up the trainer first). This worked!! I loaded up my saved game, then hit numpad 2 for the unlimited energy. Then I enabled cloaking and the voice said "trainer activated" and the energy bar never depleted. Didn't try the other options yet, though. Thank you.
[Edited by scoobots, 3/3/2013 1:37:53 AM]