Thought I'd share this with everyone. It might be common knowledge but someone out there might find it useful.

I was messing around with Freeloader yesterday to dump some of my original UMD games to the memory card. The ones I did were UK (EU) versions of Everybodys Golf, Go! Sudoku, Lumines and LocoRoco.
After dumping the first game, I moved the file to the root of the memory card and renamed it. Did the same with the rest.
All the file sizes checked out but when testing them I got corruptions with Go! Sudoku and the rest of the games all thought they were LocoRoco even though they had differing file sizes.

I avoided this by renaming the first dump, taking it off the mem card and putting it on my PC and then rebooting the PSP. Did this for all of the dumps.

I now have perfect working backups of my originals. I've heard that there is an issue with Go! Sudoku where it wasn't allowing people to save but I've not had any problems as yet.

Just thought it might help some other people out.