For second question, probably better to put it in the PS4 Save Question section, but I'm only providing the link for informational purposes in case you have to post something like this again:
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I'm not sure if it's just limited to leaderboards/multiplayer, and there definitely are some games with multiplayer including PVP that do support Advanced mode and I could swear some singleplayer games without leaderboards that don't have Advanced Mode.
But generally, yes, not every game Save Wizard supports has Adavanced Mode unlocked, and even where it's unlocked there might only be specific files you can use it on which can be annoying if what you want to edit, you know it's in another file. A lot of games are Quick Mode Only ("QMO"). Not sure if there's a way of finding out other than loading up the save in SW, or asking people. If your game's greyed out, there's no Advanced mode for it. You're not doing anything wrong. You can resign someone else's saves but can't re-region them, and you can only use SW's built-in cheats.