Game is only reques installed Steam. It's only one DRM tech that we use, because game uses Steam API (achievments, stats, cloud & workshop). You don't need broadband internet connection or something else. :)
Thx for your fast reply.
Unfortunately, I really keep away from Steam! I dont even have an account. But not all is lost: i'll play it on android.
(If/when you can make a non Steam build in the future, I'll buy it again for PC)