Someone over at gamefaqs.com posted this. http://boards.gamefaqs.com/gfaqs/genmessage.php?board=932117&topic=36488419 I tried it out and it does work. Go to the level you want to play(I did this on the 2nd autobot level.) Pick the mission with the character you want to free roam with(In my case I did the Jazz mission), I finished the mission since quitting out didn't work. When the mission is over of course you go back to the original character. (In my case Prime) Then let him die. When It goes back to free-roam you go to the character used in the last mission. I was able to free-roam as Jazz instead of Prime last night. Really silly that this isn't just a simple option in the game. But at least there seems to be a way around it.