Successfully updated to Yosemite. Started the Chameleon SSD Optimizer and it told me there was an update available that supported Yosemite. I updated Chameleon and restarted. Upon restart, there was a progress bar for a minute or so and then I got the universal no indicator (circle with a diagonal line). Have I bricked my iMac? It won't boot into safe mode. I can get reinstall OS X from the recovery partition but will that do fresh install on or will it "re-upgrade" the OS? Thanks for any help you give or light you can shed.