Yes THe invulnerbility only screws up the game when plying DS. But you can fix that. Save the game in the middle of the Juhani & Jolee battle, quit the game, and start it up again everytime you quit the game you have to reactivate certain cheats like invulnerbility and turbo.
My master will not make Palpatine's mistake. All Jedi must die. <Darth Nihl>