I too am having trouble w/ trainer.
1st i never used one that stated capture data & game crashed right away-- corrected paid attention to details
2nd is no clue what version i had; couldn't find info via game-- corrected, steam updates game automatically
3rd Tried to use trainer on saved game & crashed game repeatedly-- started new game & trainer worked
4th Game crashed again after ~30 minutes & trainer disappeared from desktop? Have to reboot PC to get trainer to work again!
crashes that go back to desktop randomly and after some time and the trainer seems 'invisible' are usually crashes that occur due to your graphics card. you can use task manager to kill the trainer in those instances, but I suggest you do some searches on crashing due to graphics card issues. I had to change my Core Voltage using MSI Afterburner to keep several of my games from crashing (Battlefield 3, FarCry 3, etc.) this happens whether or not the trainer is running at the same time or not.
there is no 'fix' for this from the trainer, since the trainer isn't the culprit for the crashes.