From webtv homepage (not tbichat site) go into Chat ... (next to messanger)
Then, don't pick the chat choices listed there,
BUT go to,= GO TO, in the upper right hand side of screen, (in smaller letters)

Once your in the, GO TO screen - enter like this:
server name = chat.braininjurychat.org
port = 7000
room = tbichat
Then hit continue to enter the main room.

Once your in the main room, look to the left and it says Rooms ... you'll find entrance to All tbichat rooms listed.

Hope this helps fellow webtv'ers!
peapod