I still can't play any of those patched games on Gen B. I thought at first it was because I converted the isos to csos, but I decocompressed one of the games and it still doesn't work.
Still? You should start over fresh with "clean" ISO rips. Also make sure you have the latest version of Yoshihiro's decryptor...the first version of it didn't work with Marvel! I think it's this one--
http://www.pspgen.com/game-decrypter-b2-yoshihiro-actualite-190027.html And this guide worked for me:
1) Open the untouched ISO in UMDGen 4.00.
2) Click on File -> File List -> Export in order to save the virgin ISO's file structure to your PC somewhere.
3) Navigate to PSP_GAME\SYSDIR and extract the (encrypted) eboot.bin file, saving it somewhere on your PC. Close UMDGen 4.00.
4) Move the eboot.bin to the root of your memory stick.
5) Run Yoshihiro's 5.55/6.00 Decryptor program and hit X to decrypt. (The folder containing his program should go in X:\PSP\GAME like any other homebrew app).
6) Find the (now decrypted) eboot.bin in the X:\Decryptor folder and save it somewhere on your PC.
7) Open the untouched ISO in UMDGen 4.00.

Click on File -> File List -> Import and insert the original file structure file you exported. Confirm that you want to force the file positions to match.
9) Navigate to PSP_GAME\SYSDIR and delete the (encrypted) eboot.bin file. Right click where it used to be, click on Add -> Existing file(s), browse to the decrypted eboot.bin, and insert it.
10) Save the new ISO as an uncompressed ISO file (I'd give it a different name/location so as to not overwrite the clean ISO). It should result in a tweaked ISO that's ALMOST (but not quite) exactly the same size as the clean ISO.