That isn't available yet, Uber is working on it but they don't seem to have a timeline yet, I expect it can't happen until at least the Early Access goes live. Mike
I'm looking forward to being able to add this game to Steam, which makes the updating, launching, and game file storage a lot smoother than it is right now.
I'm pretty sure they're busy dealing with the backlash to the price of the game on Steam like I said would happen, so I wouldn't expect the conversion thingy anytime soon.