Crossovers:
So I've listened to hours or videos and read a bunch of writeups and I honestly do not know how crossovers work.
Some (and google's AI) say that you set them in the manual section of speaker setup before using Dirac Art, but other indications are the closest you get is using the F Support Low which is a cutoff at which that speaker does not provide "support" (which is the cancellation of standing waves as I understand it), but it is not clear that's the traditional crossover point, and certainly it doesn't indicate it matters where you start.
I listened to one Direct Engineer discuss some related things, like subwoofer phase, and his reaction was "doesn't matter, it will figure it out and do the right thing". Though he did say the support cutoffs needed some attention.
So to the original question: I have no idea how it's set, and whether the setting before you start matters (because it's painful otherwise as I don't know how you get back into that setting if you wanted to change it shot of some kind of reset).
I am starting to understand ART's philosophy, though there's so much contradictory advice out there (e.g. whether or not to let the center support other speakers; the Dirac Engineer seemed to say for all speakers they should provide support unless the speaker is already too close to running out of capacity just to play).
And another mystery to me is that ART is supposed to understand the acoustic structure of the space in the room, where standing waves will interfer or re-inforce so it can act on them at different frequencies, and to do this at different locations -- but there's nothing in the measurements that provide precise location information. Is the space to the left at 2', 3', 1.5'... the system doesn't know. All the measurements seem relative locations, not quantitative distances.