Not sure if saves can be transferred, but just in case, back up your save files and copy over these. (The game refused to open when I deleted these, so absolutely keep a backup of your old files in case the game doesn't let you use these).

These saves start after unlocking OA, so Gotham is done, but with points hacked in so that you can freely play around with stages without having to do the long typing sessions.

Hacked Saves

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