Buzzen chat, like MSN Chat, is extremely difficult to write compatable scripts to use in mIRC, as the coding that these chats use does not match the standards used by most IRC networks, per RFC 1459 (if I'm remembering that number correctly.. I can't look it up right now).

I have tried to write scripts to make mIRC work with the Buzzen Chat a few times in the past, and most of the time I've been unsuccessful due to this incompatability.