5.55 umd are different than ever before.  In this and newer firmware required games, the eboot.bin is encrypted and the boot.bin is a dummy file.

The only way to decrypt the eboot.bin is using firmware of 5.55+ which has the proper decryption keys...now what my meager mind would think, if there is a way to decrypt eboot.bin, then use that file to replace the dummy boot.bin maybe then it would run?  But how the hell that is done, I have no idea.  :(  Sony has become very much against custom firmware and the benefits of ripping games to memory stick :(