Paste them into a folder on your desktop.
Update the game, then copy and paste the old files over the newly updated game files. Go play. Your trainer will probably freeze your game every 3-10 mins but if your don't use trainer you should be able to play for a long while. I have been able to get more than an hour or stability with no freeze up.
Thanks for the advice. Is there any way at all to avoid the update now and keep things as they are? Or am I basically screwed thanks to Steam? haha!