I was going crazy trying to get my saves to work. I got a replacement Nexus 7 yesterday and was busy transferring everything over to the new one. Everything worked fine except for the Titanium Backup of DraStic. It gave me a "you need to re-install" error when I started it.
So I removed it, installed it from the Play Store and then my games wouldn't load. Spent a while trying to copy stuff and forcing it to see my save states. I had no idea it'd be the different BIOS.
Thanks!