OK let me try to put it simple
The decryption is not really needed, I added it to the guide so people would know how to achieve the whole process.
The games I have reported working are not PS2 Classic, they are PS2 ISOs not obtained from PSN that have been patched with the recently discovered LIMG data segment. After patching and encrypting they will be playable on any PS3, just as any PS2 Classic would.
The process to play PS2 games at this moment would be:
- Obtain just one PS2 Classic from PSN to use as placeholder
- Unpack the PS2 Classic PKG
- Encrypt any PS2 ISO patched with the LIMG data segment as "ISO.BIN.ENC"
- Replace the original "ISO.BIN.ENC" with the one you just patched + encrypted
You can then repackage the PS2 Classic and install it on your PS3, the only step you would need to do is the activation process using reActPSN just once.
After you have just one PS2 Classic installed and activated on your PS3, you can just replace the "ISO.BIN.ENC" with any other patched + encrypted ISO you like. There is no need to be installing + activating every individual ISO with a different PS2 Classic placeholder, unless you really want to do so.