It happened with the Hellgate London trainer as well. I don't see anyone else having this issue, so I think my keyboard might be the problem. Damn you USB!
Are you sure you are using the 32-bit version of the game, both hellgate and crysis have a 32 and 64 bit version. If you use the 64bit one then the trainer will do nothing, you will get no "activated" when you hit F1.
There is another trainer which can do it. Somehow I got Razor1911 trainer after googling.
I have yet to find a Razor1911 trainer..
they've made cracks for this game, but not trainers.. and using google did NOT help..
also note in the level once you secure the harbour, and have to drive a tank, you are no longer protected except for the tank shells. this is annoying, as you need to keep replaying and saving manually for every bit you manage to proceed forward.
* Updated game trainers and cheats daily
* Get notified when new cheats are added
* Request which games get new trainers
* Priority support with any problem