run trainer, select root game folder, DO NOT run the game, close the trainer.
This should reset everything.
run the game once without the trainer to make sure it runs fine with no errors.
then close the game.
wait 30 seconds.
run the trainer, select root game folder, NOW run the game, then press F1 for trainer activation once you see your character that you can select.
Most of this stuff is outlined in the .txt files that came with the trainer.