Im sorry you'll have to do your own research on making FB's because I dont know (or remember) how to but im sure the Xbox mods and Toxin release threads should give you some info on how to.
You can find the Xbox compaitable Toxin here : http://marvelmods.com/forum/index.php?topic=610.msg11070#new
Well thank you. I looked around a little on that post but couldn't find much. Are all chars actually xbox comp if they are made into FB's?