I was referring to the UI for configuring the alarm.
The only thing that looks custom there is the pop-up buttons that
don't show a button frame, just the up+down arrows on the right. That
would involve a custom control. There was a Q&A here just one or two
days ago about custom pop-ups, the answer being to instantiate an
NSPopUpButtonCell. Check the archives.
If that's not what you mean, could you be really, really specific
about what you do mean, so we don't have to play 20 Questions?