Hello, OPA Acres!
I built a Chickshaw 2.0 in June of 2019. It has been in constant use since the young pullets were about 8 weeks old. I did not add the mild crate nest boxes until the birds were closer to point of lay.
Very shortly after adding the milk crates, I made an addition to the Chickshaw design. When raised, the nest box swivel landing bar did not cover enough of the box opening to keep the pullets from discovering they could easily squeeze past and then spend a cozy night in the nest box. The following is what I have found to work in my setting.
"Part One" of my solution was to add a hinged door that closed the open space in the back wall of the original design. This also resolved another concern I had with the original design; that of providing better security from predators and protecting the nesting area from inclement weather.
I measured the length and width of the back wall nest box opening and cut a piece of plywood a bit smaller (perhaps 1/4") than those measurements and installed the door using two hinges on the left hand side and a latch on the right side. I initially considered hinging the door to swing downward but quickly realized I would run into issues due to the corrugated panels. I wanted the door to fit inside the original opening, and in order for the door to swing far enough down so that I could still slide the milk crates in and out, the door would have to lay flush against the outside wall and the corrugated panels and metal door pulls did not allow that. I had previously added two metal door pulls placed horizontally just below that back opening so I could more easily take the weight off the kickstand prior to moving the Chickshaw.
"Part Two" involves turning the milk crates around. When doing the final egg collection of the day, which varies from late afternoon to a couple hours before sunset depending on the time of year, I turn the milk crates so that the opening faces the back wall of the Chickshaw and also raise the landing bar. The next morning, when I go out to release the hens, I lower the landing bar and turn the open side of the crates to the interior of the Chickshaw. This does not add a significant amount of time either in the morning or at coop closing. I do, however, make it a habit to release the hens from the Chickshaw and open the nest boxes just prior to sunrise every day.
The only time I had to make an adjustment to the routine was earlier this summer when I integrated young pullets into the main flock. Being smaller, they discovered they could access the milk crates at roosting time by squeezing between the top rails of the crates and the roof of the Chickshaw. My solution was to just remove the milk crates at the time of the last egg collection of the day and then replace them early the following morning. This persisted for a couple of months until the young ones were physically too big to squeeze through the space. I am now back to just turning the crates around late in the day and again in the morning.
I hope you find this of some help. Let me know if I can be of further assistance.
Best wishes!