800xA Graphics Pin Button
as far as I know it is not explained in any document.
It should be possible if we ask the product owner.
All you need a code like eg "Close all overlaps" which is located under Workplace Structure, aspect Global Verbs.
Then you add a Verb Button in your display which calls the verb implementing the "Pin".
What's the reason you want a button, is the normal Pinned Tool too small above your display ?
You know that it is possible to automatic pin all overlapped displays ?