I'd wait to buy Crysis, until they release the patches to increase speed, and fix bugs.
There are a few of them, and they are frustrating. I saw 2 people for instance and tried to shoot them and couldn't. I then threw frags at them and nothing, and yet, they killed me.
It was the right button to select the trigger. You were right
Though, I'm on a bit with mines now, and they are impossible. Theres no warning.