I am on 902 and just rooted, made a stock root backup, everything works fine. I mess with my fonts, boot anim. etc, and try to backup again, and when i tried to backup it gives me an error message saying it failed to backup /data and to open rom manager to report the issue. I opened up rom manager and there is no option to view or report the error. I then viewed the recovery log and it says "W: unable to get recovery.fstab infor for /sd-ext during fstab generation"
there is then a lot of code and at the end it says:
"Error while making a backup image of /data!
result was NULL, message is: assert failed: backup_rom("/emmc/clockworkmod/backup/How_I_Like_It")"
Not a huge deal, as my phone isn't on the fritz with the mods I put on it, but I'd still like a fix if someone has it.