for the save file resetting, it usually happen when you switch back and fro between non japanese and japanese local setting.
Non japanese save under giberrish text, but your computer can read it (usually) - although other computer won't read the same. Starting with japanese local setting after will change the text reading / writing so no reading.
Same for starting in jap then going to non japanese local.
Happened to me on older game when I had to use LE instead of switching to local. But usually, for the same game I could play and unlock everything in non japanese. But deleting and pasting the save file always failed and get a restart at 0...
So yeah, for theses game, use jap local setting all the time (LE & other emulator won't work since you need japanese local setting to write japanese in txt file).