When you finish the TIE-Fighter Constrution Facilitie Level you'll get the ROGUE SHADOW as a sub menu in the story mode. Go to extra's then cheat codes and type in the following cheats.

Cheats - Effect

wookiee - Unlock The Apprentice's father's costume
holocron - Unlock The Apprentice's Hooded Costume
mandalore - Unlock Rahm Kota to play With
jedimaster - Unlock Mace Windu to Play With
sithlord - Unlock Darth Vader To play With
lightsaber - Get a Extra Powerfull Lightsaber