I don't know whether I need to change modelers, or simply become a more diligent student of Hexagon, but my latest foray into modeling (after many years of absence) yielded the object I wanted, but wouldn't let me apply an image map.  At least, not a VISIBLE image map.  Whiskey Tango Foxtrot?!  Anyway, just venting: this post doesn't really belong here.

It's especially weird because I CAN put a procedural noise texture on the thing. Methinks I've spent too many decades as a dilettante.