Well, I see this one garnered 40 views, and not one response. I can only guess that this means it's a new one, that's not been experienced before, or perhaps my explanation was not good enough.
Either way- this post is resolved. I came home this evening, to find that we bought a replacement.
As such, like any good tinkerer, I completely disassembled the device, and tossed what I didn't want to keep.
The chassis, door, capacitor, transformer, antenna-module (MW generator?), and wiring.
If anyone needs parts for their unit, and it takes the same as mine, post back to me, and let me know.
I kept the timer-circuit board/face plate, the microswitch plate, rotary motor, fan/motor, a few sensors, and a light bulb/mount of some kind. It's the one that sits behind the portion of the chassis with all of the little 1/8" holes.
You'll of course require your own wiring/skills.
As I said- the only thing this unit no longer did was heat the food. I checked the transformer and it smelled the worst. I also looked at the magnetron and it smelled pretty wicked too, so I tossed them both. I could not ascertain whether either was actually defective or not, but I figure that 10 years 4 months is a darn good run with that thing.

I can be reached at heb113@charter.net if you want any of the parts.