I was taking a look at some of the files in the Steam RF folder and I'm actually able to play through Steam again. C:\Program Files (x86)\Steam\steamapps\common\RumbleFighter ---> RFstl.exe ---> Run as Administrator After the Windows Security Confirmation pop up, it will return with "Steamworks not initialized." Try running RF:U normally through Steam again by clicking the play button in your library or the store page. Hopefully it works for you as it did for me! Do note that this is more of a band-aid then a real fix though as after this even though it will boot, log in and play through Steam, it seems to not be recognized as active. This means it does not show up as "[your display name] is playing Ruble Fighter: Unleashed" on your profile or friends list, does not turn the outline of your avatar to green denoting you are playing, does not log play time on your profile, and the Steam Overlay will not be usable. Its better than nothing until a proper fix though! Have fun and treat each other well~
Just go to :\Program Files (x86)\Steam\steamapps\common\RumbleFighter and run the rumblefighter application as BeeBee said it does not show the you'r game time tho :3
