Dunno, let us know how that goes. Simply locate the save folder on each and either cut-paste or copy-paste between them. PC's route is C:\Users\<User>\AppData\Roaming\RenPy\Harem Hotel. Don't know Mac's for sure, but I've been told it's ~\Library\RenPy\game_directory
Yea I couldn't find the mac save so I just restarted the entire game. At least Runey did a whole revamp on the earlier scenes in patch v0.10 so more to experience