As itold mentioned on Steam, we now have Linux beta version with the latest game build. Its not public, so game will not install after you bought it. But you can try the linux branch (or beta) and give us feedback.

To switch to linux beta do as follows:

1) go to game properties

2) select "linux" beta from the list of possible betas

And that's it, your Steam will start downloading new content and you'll be able to launch and play (hopefully) after that.

Please report any bugs you'll find to the Technical Support section. We will put Linux version of the game to the main branch as soon as we confident it is somewhat stable.