In the meantime while they are working on the steam version, you can play the android version on pc using a virtual machine.
I have been playing Pathfinder Adventures on my pc using Andy, an android virtual machine that utilizes oracle vmware. It is free, but you get a couple adds the first time you run it and a couple of small "suggested games" that you can just uninstall. Other people have said that Bluestacks plays the game well too. I have been playing many of my android games on pc for awhile now using andy, I have yet to see one it doesn't run well. It is nice to play these games on a big screen when at home, and it can get you around buying some games twice that sell mobile and pc versions separately.
http://www.andyroid.net/