Ever since we moved to the latest version of FlashChat, there have been numerous problems reported. As a result, I've regressed the chat room back to the previous version, which still works -- mostly -- with the new version of vBulletin. The only immediate problem with using the old version is that it no longer handles automatic logins, so you will have to provide your user name and password to access it. The user name and password are exactly the same as your forum credentials, however.
This is just a temporary measure to get things more stable in the chat room though. At this point, I think the chat section has become popular enough that we really need to look into finding something that will integrate with the site and be more stable. I have a couple of different packages I am eying, but if anyone has suggestions, please feel free to contact me with them.