First time hatching eggs under broody black autralorps

[Leilukka]

So our egg box is elevated off of the ground with a metal ladder that goes down to the run. An eggloo. The run is caged and this is also a chicken tractor. We have 2 Black Australorp hens that both went broody. After almost 2 weeks, we got 12 fertilized eggs for them from another backyard chicken farmer. Heritage Barred Rock. There is an open door that goes down to the metal ladder. Then there is the back panel that opens out. There is a roosting bar that is plastic that sits on another tray. We filled this in with both pelleted pine shavings and some pine shavings. The front door to the ladder is open and the hens are up against the back panel. We cannot open the back panel without the possibility of an egg falling out. We learned that the hard way because we have witnessed 1 egg fell out from the back panel when one of us opened it. 1 egg rolled out the front door onto the ground of the run. 1 egg was cracked all around and so cleanly eaten from inside that the shell was not sticky at all. After all of this, I added more fluff in their coop/egg box of pine shavings. So we are down to 9 eggs and 2 hens.

For the past 4 days the hens have not left the coop/nest box at all. I have been bringing them food and water once to three times a day.

I am worried about what to do when the hatch happens. Will the chicks fall out the front door and get terribly injured?

How can we keep these 2 hens healthy, prevent egg breaks, and prevent chicks who hatch when we are not there to fall out from the front door?

We have around 6 trees in our backyard. Usually, we let the hens free range in our backyard since they were out of sight from all the tree cover. These are the only 2 hens that we have. The run is small, perhaps enough room to accommodate 3 big hens.

Do I keep the usual free range hens locked up in the run with the new chicks? If so, for how long?

Do I need to put down a thick layer of pine shaving on the run dirt floor? If so, how high?

Any other suggestions?

Thank you. This is my first time and the hens' first time.

 

[Yardmom]

Sorry I'm not picturing the set up, but I would suggest having the hens go to food and water instead of bringing it to them. They need to empty waste (poo) away from the nest.
Chicks can handle a hop down, (how far?) But won't be able to go back up.
How to handle free ranging will have to be up to you. My hens have access to free ranging soon after hatch, but my hens rarely take the chicks out the first weeks.

 

[Leilukka]

Thank you. How do I ween them from expecting me to bring the food and water? At most, I went out there 3 times in the day.

The coop/egg box is around 2 1/2 feet off of the ground with a metal chicken ladder.

I'm concerned that the run is quite small because normally the hens get stressed when we have left them in the run for safety when we're gone. Do we need to purchase a large dog kennel? The kind that you can stand up in?