Currently VoidExpanse should work fine on Ubuntu, Fedora and SteamOS.
However there are some known issues:
1. visual glitches and artifacts (especially on AMD and Intel GPUs);
2. random crashes;
3. cannot launch the game (especially on quiGPUs).
If you have any of these issues, please add this launch option to the game:
(right click on the game in Steam Client, select Properties, click on button "Set launch options" and paste it there)
If this not helps, please try adding this option as well:
It will force the Unity engine to use old OpenGL2 renderer (which is in some cases more reliable).
If you still have the issues, please upload your Player.log file from the folder "~/.config/unity3d/AtomicTorchStudio/VoidExpanse/" at http://pastebin.com/
and share the link.