I noticed something interesting today: After playing PSO V.2 (Region NTSC-U) I loaded the Ives modified disc image of PSO (Region: Free) for loading into Sylverant which shows up as V.1 in the GDEMU menu, but is actually V.2. When I started the game up it asked me to enter my serial number again. Confused, I shut down the console and loaded up the vanilla disc image which didn't ask me for the serial number meaning it's still saved to the console OK. I then went back into the modified disc image, entered my serial information a second time, and had no problem loading my character up. Although it did ask me if I wanted to convert to V.2 even though it was already on V.2. (this was a little scary, so I backed up first.) I was also curious about if it would relock an unlocked file, so I went ahead and disabled the copy lock on the save file first.
After loading up the game I saved and exited, then I loaded up the unmodified game. It did not ask me for the serial number, but neither did it let me load the save. "This file cannot be used to play the game." so even though both discs are V.2 it definately required conversion and you can't go back on it (without having a backup, of course). That means I won't be able to use overclock with my GDROM unless I burn the modified disc image. The save file was locked again though, so I went ahead and unlocked it again to see if it was locked by the conversion or just through normal saves. Unfortunately, once the file is saved over it's relocked so I won't be able to use the normal system menu and a second VMU for quicker backups.
It occurred to me that there must be a reason why this modified disc image would not be able to read the serial number and access key already stored, so for one reason or another the game thinks of it as a separate game. If that's the case, however, might there be a simple technique for making small modifications to disc images so as to allow more than one person to be able to share a console for playing PSO each with their own serial number?
Not that I personally care about that. I plan on having a different console for each person in my house. Regardless, I find this potentially useful since I have an old character with a Serial Number I can't access. I imagine that if I could create a new disc image for the sole purpose of using a different access code it might be possible to take it online in the future. It's also useful for people who don't want to wipe the memory of the console when they can't find the code that's stored on it and also potentially useful in situations where you have more than one, don't know which one to use, and don't want to risk all that much. A limitation though is that once the files are converted they won't be able to play on an OEM disc anymore which makes this idea extra risky.
Possible Use Case: Suppose someone started playing with a shared access key, but wants to start playing on their own key. If they can connect to a private server with the shared key and backup their character then connect with a new character on a registered access key maybe the server would be able to change the new character to match the old one, excluding story and bank contents, allowing a system of access key migrations to occur. While I imagine that should already be possible with multiple consoles, having the ability to store multiple access codes on the same console would make the process easier, or so I imagine.
I wonder what exactly makes this work though.