Can you explain a little more about "you save a game disk"? It seems like WriteSaveData is more akin to JS cookies, that is, not terribly useful for saving multiple distinct savestates (unless you put slot number as a prefix for your keys).
Sorry, missed this. Discord is the best way to get quicker responses. In sort, WriteSaveData will add whatever you pass in to a file called saves.json in your game's folder. If you build a .pv8 disk from the workspace explorer menu, when you load that disk it will save the json file inside of that disk. When you share that disk with other people it will have the same save file in it like old game cartridges. I uses this in all the tools btw, that's how they retain state between sessions.