Just ran into the same issue (flip scrolls over the “sticky” nav bar pro).
Ran a search and found this (glad the search takes two search words BTW).
Haven’t tried the Z order thing, as I was having other issues getting it to format the way I wanted and scratched that for a button triggered Modal, which is working fine and takes up less space on the page (it’s just to show a graphic with the product dimensions).
However it may not be a bad idea to put a note to that effect on the flip documentation page (i.e. if using with Nav Bar Pro set the Z order to 1100).