Hi Rob,
I used to have a Maggiolina for many years so I'll try to answer your questions.
"I did figure out to tuck the inside flap under the mattress, and that's why I didn't get too freaked out. Seems like it would work, but it's a bit fidgety. Couldn't they use a zipper that turns a 90° corner to zip along the bottom, similar to every other tent? Seems easy enough, but maybe I'm missing something. And how important is it really to have the windows open for ventilation? Will it condense inside if it's not?"
Condensation isn't a problem, the Drylon fabric is like a mesh with thousands of tiny holes so water vapor passes through easily. The windows are triangular so it is easy to control airflow. Maggiolinas are very warm tents, I remember camping with my wife 7,000 feet Donner Summit in December and having to shuck off coverings in the middle of the night. In high winds at high elevation you can feel a little breeze inside the tent. The winter hood is designed for that, turns the Maggiolina into a double walled four season tent.
The old doors and panels were designed to be replaced or modified. You can drill our the rivets up top and unclip the bottoms if you need to work on the fabric. The doors if I remember are designed to be replaced pretty easily, if the mesh is damaged for example. I would recommend using the tent for a few months before you make any changes though. A lot of input from a lot of people around the world have gone into the tents. They try to keep things as simple as easy as possible.
"What about the light system? I see the light, but don't see any wires? Are LED light bulbs available to replace that bulb?"
LEDs I think last about forever but personally I don't like the glare that comes from them. You can tap into the wire there and add stuff like and outlet for a computer, fan, or in my case, chart lights for reading. I like the light from halogen bulbs. The power wire should be coiled up next to the door. AutoHome normally leaves it bare so you can add a cigarette lighter plug or alligator clips, whatever works for your vehicle.
"Can I use a drill to open and close the tent?"
Yes, Mike should have some adapters. Always a good idea to have a spare crank. I left mine in the tent and drove off in the morning and it fell off somewhere. You realize there is no way to open the tent without a crank, it is like a key. A really large screwdriver will work but it takes forever and is a real hassle.
"Is there any really good owners manual? I guess I have a billion questions, and the little thing it ships with is too brief."
Good point, they are always changing the tents and have all sorts of undocumented improvements. Mike was showing me his new Maggiolina and it looked like they added a couple loops above and to the side of the doors to hang an awning. AutoHome will add stuff without telling anyone, they seem to be alway undergoing testing. The benefit is you can retrofit so your tent doesn't go out of date too fast. It is sort of odd having to try to figure out all the goodies in your tent. The owners manual is more of like what not to do, after that anything goes, make your tent your own.
Mike has added a blog to the AutoHome website. I just wrote an article on retrofitting the older Maggiolinas for awnings. He is encouraging everyone to add their suggestions and improvement. This should help a little, but you are right, not all features are explained.
"I noticed when it's open, that the frame isn't super stiff fore-aft. Anybody find it moves around a lot with winds?"
Your Maggiolina can take more wind than you can. The side walls become sheer walls and the tent is really strong when the fabric is tight. Only trouble, it is difficult to sleep in very high winds, there is a real racket outside, like trees falling. In those conditions, get out, close the tent and find someplace safer and quieter for a good nights rest.
"Does it really only need two racks under it? That's pretty cool. I like the idea of being able to use it on our minivan sometimes, but I'm sure it's well over the "weight rating" on the factory rack. What's the reality of that situation? I see some people are using them on small cars with Thule racks and such. Nobody really publishes static ratings."
I was amazed too when I got my tent but two bars is all you need for most cars and trucks. You can add more if you wish, but is isn't necessarily needed. Mike showed me the results from AM General's crash testing of the Maggiolina and Columbus, they were impressive. They both survived a simulated 45 MPH crash test with no issues. I don't think static ratings are a concern because the racks are usually tied into the roll cage of the vehicle. You are right about most of the manufacturer's roofbars, they are usually pretty wimpy and I don't trust them. Thule and Yakima make some well engineered bars, and they will give you a weight rating.
"How do I know when I've got too much stuff stored inside? As long as I can reasonably close it, I'm fine?"
The top will not close, seriously, you want to have light fluffy stuff inside the tent. Good place for the ladder but be careful of "point" loading, where a lot of pressure is in one small point. It can cause the fiberglass to flex and the gel-coat will crack around it in what is called a spider. It is cosmetic but the finish is so nice, why damage it. The Airland is designed to be as sleek as possible, not much other than bedding can go inside. The Grand Tour has an elevated roof so you can load a lot more inside the tent.
"Any reason not to mount it backwards? I'm designing my trailer such that the top of the tent will be level with the top of the truck, and I figured it would actually be more streamlined sloping to the back. I noticed the "front" has two clasps and only one on the "back". Maybe since the tent is in the slipstream of the struck, one clasp at the front is fine?"
Should be fine, I've seen it done. There has been a lot of testing to make sure the tent has minimal wind noise. Wind noise is drag, cuts into your mileage. If you hear noise, it would be a good idea to test and move the tent forward and back on the mounts to find the sweet spot where the air passes freely around the tent. The clasps are really a redundant feature, to keep the two shells from working against each other. The tent will not open without the crank. If you are concerned, ask Mike for a couple more clasps, they are easy to add.
Hope this answers this batch of questions. I'll be adding some content to the AutoHome blog from time to time. In the meantime, I would be happy to help, I know Mike can get really busy.
Rich H