will the 2 players playing the henchmen be able to customize characters from scratch?
Not with the mod not currently. Sorry:(. They will get the characters as you get them normally and then from there they can customize them. I have a method for changing the characters stats (if you haven't recruited them yet), but I have not found a way to give points to spend. There's a mod thread where someone is looking into if you're interested. That's found here.
http://www.larian.com/forums/ubbthreads.php?ubb=showflat&Number=505972#Post505972 . If you were willign you could edit the stuff manually for what your other players want.
