I'm afraid it is not possible to move any players/non-players between clubs or make them free agents in saved games. I don't have the full saved game structure and so I cannot process/edit the additional tables in the saved game which contains the additional contract data. So you'll find players will end up in some strange limbo in-game if you try to move them. I will try and make this clearer in the next release of the Editor. I would treat the Editor as a saved game viewer rather than a saved game editor.