I've intentionally not mentioned who supplied the profiles to me, but suffice it to say that they should be -THE- go-to company for providing them.
We've been on the phone and they're looking into it, and we've got some other tests to run, so I'll give it some time before I bother anyone on LuLa.
I'm starting to wonder if it's the latest manifestation of the usual mix of Apple/Epson/Adobe issues.
I tried converting the colorspace of the image using that profile, one with RC and once with perctp, and then layering them in photoshop, with the "difference" blending mode. That does indeed show the problem fairly clearly with these new profiles vs other, older ones.
If we can't figure it out, I'll head over to LumLand and see if they have any ideas. Thanks for that suggestion.
More here when/if I find out something new.