Before making a scripting solution, I wanted to double-check that your problem isn't because of an unwanted setting checked.
In mirc-options/IRC
there's a group of 6 checkboxes on the right side, one of which is for notices. If notice is checked, mirc shows it in your active window instead of being where it "belongs". I just wanted to make sure you weren't wanting this scripting window because you have several channels open, and notices from each unrelated channel were following your cursor around instead of staying where they belong.
Also, in my experience the receiver can't tell the difference between receiving an onotice vs a normal notice, as the onotice command just figures out who's an op and sends the notice to them.
