It might, as long as they can see them, which is why I asked if there's evidence of them exploring the boxes at all. My nests are at floor level and I still had birds that never put their heads in to look, so they had to be physically put inside to "see" the boxes.
Possibly. Chickens can adjust but are the nests at a convenient location for you? Have to weigh the keeper's needs as well as the chicken's.
I'd replace with fakes, because real eggs are obviously more prone to breakage plus they're better off eaten. ;) Golf balls are a cheap way to do it...
32" up should be ok as long as you don't have breeds that can't/are too heavy to fly/leap well.
Bigger question is, are they even aware the nests are up there? Have you seen any evidence of exploration, i.e. kicked around bedding?
Hard to tell angle but if it's around 45 degrees (or more) it's likely too steep.
I'd consider removing the ramp, actually. There's a good landing lip in front of the boxes and they're not high up, so the chickens should easily be able to jump up there if given the clearance to do so.
Is the...