thanks to Greg's other thread, I found the answer to my problem, hope it helps you:
1. I had backed up my TA per http://forum.xda-developers.com/show....php?t=2292598
2. That enabled me to restore the TA from backup (based on the little reading I did beforehand, as long as you're not on a custom ROM you don't need to downgrade first)
3. I simply re-followed the instructions in NUT's main thread to try again to install his 757 ROM
My camera works now.