MemberGate itself intentionally does not have a chat room function for the following reasons:
1) It is server intensive for resources which can cause server performance issues
2) Chat room content does not contribute to long term content on your site. It can dissuade people from
using the discussion forum (which does stay on your site) as opposed to a chat conversation which disappears.
3) They may present security issues as it opens a peer to peer connection between member computers
There are some MemberGate owners that use a third party chat service like at www.addonchat.com
They post a new weekly chat room password into the members area of their site. You may want to consider
only having the chat open at specific times initially to judge whether it would be effective or not on your site.
Remember that having it on without supervision can result in potential disgruntled member conversations...