ADE 9x Photoreal Scenery

How would one add a photoreal ground texture to an airport in ADE? Adding a background image doesn't help (the image isn't compiled with the scenery), and I can't find anything in the polygon menu that will do what I want.
Flight Simulator and other chat
https://forums.simviation.com/phpBB3/
https://forums.simviation.com/phpBB3/viewtopic.php?f=16&t=38974