I'm on a Mid 2012 MBP with Mountain Lion. I recently enabled FileVault on my boot SSD drive as well as encrypted my other hard drive I put into the optical bay. So far, so good.
However, each time I boot my desktop background reverts back to the default "galaxy" background that shipped with my MBP. Both my boot and secondary drive have their passwords stored in the keychain, so after logging in OSX should be able to see my background image.
I've tried placing the image on my primary and secondary drive but neither made a difference.
Is there some sort of trick I'm missing to get my own custom background image to stick after a reboot? I've even tried changing to a different default background image that ships with Mountain Lion, but even that reverted back to the default galaxy image.