Had a similar thing happen except in my case the scene reverted to wireframe which I rarely use and all the lights had just gone, they weren't even in the scene! Lost everything! It "SEEMS" to happen if you do a save after a failed render, that's my experience anyway so if I get a failed render now I just close the whole thing down and don't save when it asks. I haven't had this issue since doing that! Definite P6 glitch IMHO! thefixer, poser coord.

Injustice will be avenged.
Cofiwch Dryweryn.