Marlin and E1 else thanks for the tips.
Going just on intuition, the outback oven has seemed to me like good bet for a lightweight, packable, multi-use addition to the kitchen gear; and based on the reviews I do intend to try one in the future. Unable to pull the trigger on buying one yet though.
So far I have been unable to find any foil insulation in my area. I did call one of the companies that manufacture the stuff, and they did not recommend it for use around food, near flame or for temps over 200 deg. The guy I talked with said the foil is 99% aluminum with 1% of some type of fiber that wasn't good to breath the fumes of. He didn't mention anything about the plastic bubble wrap. Perhaps after fully heating the bubble wrap foil a few times the problem of noxious fumes is solved? He recommended trying aluminum foil to build an oven.
Recently I aquired a 6.5 cup jello mold from canoefly on the bwca site. Since I only wanted one jello mold, and he had some extras from ebay, it seemed like a good deal for us both, thanks canoefly! Made a heat deflector yesterday from a $1 round stovetop burner ring by using 3 stainless steel bolts for a riser (based partially on a plan from canoefly), and put a pot lid with vent slightly open on top to trap the heat. We have a silicone baking sheet, and plan to try incorporating that into use for a lid in the future, perhaps with a way to view the contents without fully removing the lid. The whole contraption with a metal lid weighs just over a pound, not including the nuts and bolts.
I tried the oven out last night with a Krusteaz, fat free, just add water, honey cornbread mix. I used an MSR dragonfly, and set the burner as low as it would go without the flame going out. The stove's wind shield fit nicely around the oven. A small baking thermometer placed outside on top of the lid confirmed a temp of around 200 deg. Forty-five minutes later the cornbread was still not done, and I slowly kicked the heat up a bit until the thermometer read 250. Long story short, I ended up finishing the approx 1" thick cornbread indoors in the kitchen oven. The bottom and top edges finally came out lightly browned.
I did bake a few 'control' muffins indoors to see how I liked the mix. They are edible, but I can honestly say that I prefer the Jiffy mix that requires egg and milk. Will try that one with powdered egg next time. The final results on this round of indoor and outdoor baking was fairly similar, although I did finish off for a couple minutes indoors.
One thing that I initially forgot to do was to quarter turn the pan to insure even baking and will remember to do so sooner on the next test. 'Poking' the cornbread with a metal skewer (out of toothpics) confirmed some parts were cooking faster.
It seems that I was afraid of burning the cornbread on my first try based on the 1.25 hr. long baking time and undercooked results? I did wait about 25 minutes before taking the lid off to check it the first time, but ended up checking several times throughout the process. Next time I will try kicking the heat up a notch, add a few minutes for preheat, and keep my fingers crossed.