Can I send private messages to other users?
Yep! In the user list, just click on the speech bubble next to a person's name and select "Send Private Message."
Can I change my name?
Sorry, you cannot. The chat room works directly off your site username. The plus side to this is that no one can impersonate you, other users, or myself.
How do I change my avatar?
Ah, sadly I'm still trying to figure out how to sync user images to chat avatars. I can disable them altogether, but only if I pay Chatroll... $200... a month.