I haven't seen many installation posts and I wanted to share something I learned while per-assembling my NexDome Kit concerning the doorway.
I quickly learned that the door gasket doesn't go on easily around the door opening. Since it comes rolled up it has a set twist which makes it difficult to lay onto the door frame ridge. In order to increase its flexibility I unrolled the gasket and laid it over one of the box tops from the dome kit out in the sun to soften up. It sat in the sun for about an hour and got warm and pretty pliable.
It takes at least two people to pre-assemble the panels. I had set up a table do most of my pre-assembly work which turned out so I wasn't working on the ground. The table provided a very solid surface for the panel pieces and the door itself. However, the door frame panel is very floppy in nature so I took the box top from the same shipping box top, that I used to heat the gasket in the sun, and laid it over the table to give me a large flat surface to support the door frame.
I found that I couldn't push the gasket hard enough to slide it all the way on the door frame ridge. I then got my trusty rubber mallet and gently started to tap the gasket onto the ridge. Tapping didn't work so I needed to increase the force to hit hard enough to push the gasket all the way on the ridge and not to hard to crack the door frame. During the hitting of the gasket my helper held the door frame up so I could attach the gasket and not over flex the door frame. I have a few photos that demonstrate the difference between pushing and hitting the gasket.
I hope this helps.