For anyone updating from the old engine to the new engine version, make sure to grab your save files from your android/data/lust.odyssey folder beforehand. This folder is locked on newer androids but you can use a pc to access it or shizuku with wireless debugging.
Then when reinstalling the game and the newer version you can plop those save files into the newly created lust.odyssey folder in the android data directory. The older save files thankfully work on the new engine, get a warning they were made on another device but that's a false flag.
Stops from losing progress!