Would you mind sending us a log file to check what's going wrong for you? You should find one in ~/.config/unity3d/Semaeopus/OffGrid/player.log. Just send it to support(at)semaeopus.com and I'll take a look. The build's been tested on Ubuntu 18.04 with proprietary nVidia drivers, at the moment I really wouldn't expect the open-source nVidia drivers to handle it. And as far as I'm aware, others have ran it in Ubuntu and Arch at least without any problems.