Skin colour might be a demo thing. Never played the JA demo, so can't help there.
The best way for getting rid of the powerful evil jedi is to use the caverns as your friends. Force grip and toss 'em off. You have to do it fast, because they won't stay wriggling in your grip for long, but you can just grab 'n' toss if you do it fast enough.
Be considerate to others or I will bite your torso and give you a disease!