The only problem I see if two people have the files loaded would be that they'd try to update at the same time, and you might get the socket in use error? Maybe not? I'm not sure if the socket in use error is only from the mIRC side, or if it's coming from the website. I have no clue how that socket works.
Sorry for not answering about PS1, didn't see it. I think it'd be quite difficult to implement because some people come in and change their nicknames to whatever, or others will come in as guests. It's a good idea, but would only be feasible if it was strictly a member-only chatroom with no guests and the members never changed their usernames. Even then the scripting of that is beyond my knowledge.
For the topic, try changing your topic in the chatroom and it *should* update the topic on your website. Let me know if it doesn't do that.