daug: Found a solution.
Just use LC_ALL=C command before launch the game.
Great find! Thank you. You've saved me lots of time.
I've just wanted to tell you that I've encountered the same problem on Arch Linux.
Aditionally the game set the mouse scroll speed to some crazy number on each start and during the placement of factory modules, the module didn't stick to the cursor. All these problems seem to be fixed.
Have you observed the same problems or are they specific to LANG="de_DE.UTF_8"?