After installing the newest update to OS X Yosemite beta, factorio crashes instantly, no loading screen appears at all. I'm running factorio 10.12.
I understand that it can be difficult to make sure the game works on prereleases of operatingsystems, and that this might solve itself with new releases of Yosemite, so this is more of an FYI, thought you should know, kind of thing.
Here [1] is a link to a pastebin with the problem report that appears at the time of the crash.
Of course, if you can fix it, it would be amazing, but I'm not expecting anything
Love the game, and hope I'll be able to play it again soon!
[1] http://pastebin.com/U4BkEuAE
