Not curved edges, cured edges. The PL300 is an air/moisture cured product. If you spread it out evenly the areas around the edges that are exposed to air cure rapidly. This causes an air seal and keeps the inner part of the field from curing.
The inner part away from the edges stays wet and doesn't adhere much at all.
This product is only intended to, essentially, tack the foam in place on a wall until you come back with your finish panels and mechanically (nail, staple, screw) attach them to the substrate, thus also mechanically securing the foam. Also by design, if used per OEM instructions, if you were doing a demo, the foam would be relatively easy to tear out, just a few beaded areas to scrape off.
Most of us foamies are looking for more of a unitized construction method where the foam helps hold the panel rigid to form a stressed skin, or structural diaphragm.
I suppose that's a little off track for your build purposes, but I figure everyone is watching, right?