Its not as difficult as it looks.
I did not finish the “foot end” in the test I made so it was open. The foot end would be the last thing I would do after I inverted the fabric. Could also be done if there was an opening for the pad. I did not make an opening for a pad ( I forgot) but because it was a scale test it doesn’t matter. I would have if it was a full size.
Loops for tie-outs can be added later. They don’t have to be between the fabric and the zipper but they could be.

To prevent a floppy opening you could add some Velcro. Just a few small strips would do the trick.

I made another small video demo today but I haven’t got the time to edit it. I expect it will be online Wednesday.
I don’t know how Papasmurf get the nice clean look but I guess he uses the coil on the zipper as a guide like me.
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