the pip hotkey is attached to a pip and the original window in that region.
when you hit the hotkey, that window will be brought to your current region
hitting the same key more then once within the same region will do nothing, as the requested window is already there

as for maximizer layouts, you can use the import / export capability within maximizer
(there is a bug in v1.8j with the layouts not exporting the resolution for each reigon.. that has been fixed with v1.8k)

i hore that answers your question. if not, feel free to drop me a note.

have a great day,

Rob