Just a quick update:
The little girl has been chowing down on her hay and rolled oats, and drinking well. Stool looks good, when I offer her a bit of calf manna she eats it right up. (Hope it's ok, I'm just giving her perhaps half a teaspoon twice a day. The fact remains that she's shedding like crazy so common sense tells me she needs some protein to replace it!)
I'm also making a point to groom off as much of the loose hair as I can.
I don't think it was cocciddia. In her former home she was kept in very clean circumstances on wire her entire life, with ACV in the water at all times. Since she's been here, it's been similar circumstances. Basically no place to pick up cocci, right?
It also really doesn't seem to be a hairball, no tight distended belly, no string of pearls, her appetite is improving.
I think I may have just ended up with a rabbit that is somehow exceptionally prone to stress, and moving and molting and going to a show all at once, perhaps, has done a number on her.