You need a 2Mb cart in the passme in order to save.
Yes, it will overwrite the save data in the retail cart no matter you choose where the save should go in the patcher.
Wow, I could play this game without seeing the ending and without being able to save? I think I'll be perchasing the quality product. *shot* Seriously, I need to get a game with a 2Mb FLASH save.