[Q] Need advice on wicked S5 rom topic

I installed the wicked s5 rom on my Sprint Samsung galaxy s3. Everything went fine, no problems with the rom, it is great. I wanted to go back to my old rom to get a file that I forgot to back up, but when I restore my backup after it boots up when I go to my home screen I get a box that pops up that says google has shut down, if I hit ok, it will pop back up, there are some others also, but I cant remember what all of them said. I also tried other backups I have and would get the same thing, every time. I installed the backup I made of the wicked s5 rom, and it works every time. I have done 5 or 6 roms on this phone, and never had a issue when going back to my backup. I never do a dirty install, always wipe everything, has anyone else had this issue? Thanks..