Buzzen is NOT an IRCx server. Buzzen's protocol is proprietary to Buzzen alone. Do not expect any code from a buzzen connection to just work fine for another chat network. ( some code will, but Buzzen's IRCwx protocol is different than any other chat network)
/names $chan
This will send a query to the server to give you the list of nicks in the channel. Returns on raw 332 or something like that. This is what tells mIRC what nicknames are in the nicklist. It also gives you topic and welcome message.