Correct me if im wrong...

on @*:nick: ...

That triggers when an OP changes the nick... Doesnt make sense. I changed it, and also implented some other functions.

Code:
on *:nick: {
   if ($me isop $chan) {
      if (guest isin $newnick) ||  (unknown isin $newnick)
         inc %nickkick
          kick $newnick Identify your own nickname, or change to another by typing /nick [NEWNICK] ! [Guests pwnt: %nickkick $+ ]
          }
      }
  }