There are some commercially produced screens out there, but due to the unique nature of the sliding side door, they are EXPENSIVE! Joyce happened across some white tulle (a LOT of white tulle, actually). At first it seemed almost ideal as it was light and flexible and fairly strong. She made a screen for the rear using the old fiberglass screen as a pattern. It came out okay. Then we tackled the side door.
I found some curtain track that I mounted on the inside. It has free-rolling hooks to hang a curtain (or screen) from and would easily roll back to open. Joyce, then began trying to construct a curtain from the tulle. Not pretty...
She sewed elastic along the top. The elastic had small holes along the length which were perfect to hook the screen on the track. That part worked well. Next was how to secure the screen to the perimeter of the door opening.
I chose Velcro and magnets. First, I glued a long strip of Velcro "fuzz side" all down the front of the doorframe and Joyce sewed Velcro "hooks" to match on the front edge of the screen. That was when the trouble began. The Velcro hooks on the screen would grab the tulle any time it touched it. It was like trying to put down a feather with sticky fingers. We would have to swap and put the hooks on the doorframe and the fuzz on the screen. But, before we made that change, we realized the tulle was so light and flimsy that the slightest breeze would billow it out and it would require some method of securing, not only to the rear of the doorframe, but to the bottom as well. This was becoming a big chore. We decided we probably needed "for real" mosquito netting instead of trying to make do with fiberglass screening or tulle. Since we were going to St. Louis to have Pumpkin checked out, we planned on hitting the fabric stores there to find some proper screening.
Dusty to the rescue! As we discussed with Dusty what we were trying to do, he remembered he had a large portable screen room stored in the attic that he hadn't used in years. He offered it as a possible source of screening. We could cut sections out of the sides if they were big enough and it appeared they were.
Mosquitoes have met their match, I think. The side door curtain/screen is easy to close and easy to store. The rear door screen will be stationary, but has a zipper down the center so we can access the doors from the inside. We are both very pleased with the outcome. Thanks again for the screen room, Dusty.