can't do that with steam
You can actually

I had to do it with Manhunter (yes, old game i know) as the steam version refused to work. I was able to swap the .exe file for a previous version, to be able to get the game to run. (Loads of posts about it if you search google)
Assuming you could find the first version .exe file, you should be able to swap them, as long as you don't verify the integrity with steam.
Is a bit annoying, though it can be done.
Though personally I'd wait for the next patch/profile to be released, both of which are this week.