I installed Outerra yesterday and I swear I had atmosphere rendering. A change to fullscreen followed by a restart --> no more atmospheric rendering. I tried everything, deleting config files, and performed a full (Program Files & Users/me/Outerra/) uninstall/reinstall. Nothing. I did notice that there's only one file showing up in the /atmo directory, that file being the stars.
Any ideas? (And yes I've verified the sun was overhead)
P.S. I would have done this through xTrac in game, but it doesn't seem to be connecting...