Try clearing your cache, temporary folder and those two "white" files.
I did try to change browser to google chrome instead of firefox and download the trainer from there but same thing.
Edit: Cleared Cache and temporary files and all the white files are erased, but i still get the message when i try to activate the trainer.
Since my game is on steam, the other trainer i have should work, i just hope it does not happen again.
[Edited by sauced, 6/12/2012 2:18:52 AM]