heheh sorry...
after you add it to your remotes you either restart mIRC or type /bnc.start then it will ask you some questions, and you fill in the answers. I'll give you an example:

It's gonna ask you for a nick, ident, full name, server, server port, port to listen on, and a delay in trying to reconnect.

Bob is Steve@this.is.a.hostmask.com * Bill
Bob is the nick mBNC uses (obviously)
Steve is the ident mBNC uses
Bill is the full name mBNC uses

the server port is what mBNC uses to connect to the server (6667 for example)
the listening port is what you use to connect to it

It doesnt have multiple users yet, so if you arent planning on using it, then just setup the info for your friend and make sure the port is forwarded so he can connect then tell him to type /server
So if your ip is 1.2.3.4.5 and the port to listen on is 12345 the command would be
/server 1.2.3.4.5 12345

And that error you got.... i thought i added protection so that wouldnt show.. guess it doesnt work sometimes :< that just means that it tried to send the info (nick/ident/etc)
to the server, but the server had already closed, or it never opened...

Hope this helps! And sorry for no instructions :<