How members access to ChatRoom if no one is there?

Hi there,

I am curently using ChatRoom module. I have created a Chat Room, so that everyone could access. I only want to display the ChatRoom by a block. However, when I leave the Chat Room (when no one is in that chat room), the ChatRoom on my left block will disappear, so no one could access to that ChatRoom. How could I create a ChatRoom and display on my left block permanently even though no one is in the chat room and they can access to the chatroom at any time. I do not want to let members to create their own chatroom currently, because I will face difficulty in controlling them.

Thanks for your advice.
Have a nice day and sorry for any inconvenience caused.