1. There is a UMD dumper that saves the dump in a .ISO format that comes on PSPFiler, which can be found
here. Once you put PSPFiler onto your Memory Stick, you should load it up, select a language, and press either X or Triangle; both of them will bring up different menus; only one of them has the UMD ripping function on the menu; it will tell you what button needs to be pressed to use it.
2. Patch the .ISO that is created like normal.
3. Use SGDeemer, which can be found
here (I'm not sure if this is the latest version; I've never used it before), to create a decrypted save version using the original .ISO that worked with your save game (I have no experience with this, so I'm not sure what else I can put here).
4. Try to import the decrypted save from your dumped UMD .ISO and re-encrypt it (Again, I've never used this, so I don't have anymore information).
5. It should spit out a save that works with your UMD.