I just took these pics.
I'm not a carpenter as is clear but it's strong and works. I put the gutter and downpipe on because the laying boxes ended up bigger than planned so the water would have dumped onto the lid. The gutter stopped that and extended the roof out over the lid too.
The back of the laying box is a door hinged at the bottom, same as the entry door and has 4 compartments in case they all want to lay at the same time!