why would you use a chatbox for a RP?
just stick with the thread until you feel we should
make synoposis on what's happening so far
and what the characters are...
places in the story... etc.
and make a new thread that's more nicer and organized
and give everyone a chance to RP
if someone has to post next then PM them about it
or put it in the post in "()" "[]" whatever to show
it's not part of the RP