But as far as I've understood your efforts you don't know the encryption algorithm or the key which is used by the PS3 to decipher the backup so the entire project won't result in a possibility to inject homebrew code, will it?
Please don't get me wrong, I really appreciate the hard work done by some members here!
Good luck anyway
If I've followed this project correctly it looks to me like those tools are only "injecting" some (random?) bytes which the PS3 doesn't refuse when restoring the backup.