Time for an update.
I've been doing a little bit now and then....
I thought I finished the door
But after being outside in the rain, a small amount of water is running under the door. I might have to add a piece of something across the bottom of the door. That's the bottom in the picture where there's no gasket

I also started on the inside. I cut out the foam in the front so I could have access to store things. I'll add a lip across the bottom to keep things from sliding out.

And I cut the bed platform in half. I'll hinge the back half to access the rear compartments. I'll take out the middle piece so I can store the popup under there.
That'll leave the 2 side compartments. The front of the platform will be secured in place.

Here's a picture from Mikes thread showing the foam compartments .

After cutting out some more foam, I'm going to cover all exposed foam with canvas to protect the foam, and keep it from deteriorating.