I couldn't find an answer to this elsewhere, so here we go... I'm using linux mint 15 atm, and the ksp freezes on the very end of the loading screen, I can see the bar fill up, but nothing happens then. I get no error message, if I try launching via the command line. no mods, deleted settings.cfg to be sure... EDIT: Due to copying the files from existing installation, the permissions were wrong on home/"user"/.config/unity3d I deleted it and downloaded new client, works now on linux mint 15!