Here is the whole thread:
https://www.backyardchickens.com/forum/viewtopic.php?id=21498&p=1
And here is the summary:
For anyone searching for info on crop problems in the future (as I spent hours doing) here is a recap:
Initial Symptoms: very full crop that did not empty at night, not rock-hard but pliable like modeling clay, could feel fibrous material. Thin bird. "Dandruff" of flakes off the feather quills.
First treatment: Isolated bird to dog crate inside, on newspaper so she wouldn't eat any more fibrous stuff and I could monitor poop. Massaged the crop for 5-10 minutes periods ever few hours. Fed water with raw apple cider vinegar (a small splash in the waterer) and plain live-culture yogurt mixed with baby-bird-food from the pet store.
The next day her crop had partially emptied but still had some finrous, clay-like solids. Fed more of above foods, plus bread loaked with A LOT of olive oil, and later with mineral oil. More massage.
New symptoms: Perhaps due to the strange diet, her crop blew up again but different: soft, squishy, gassy and balloon-like.
Threatment: Continued with massage. Stopped the yogurt and ACV in case they were responible for the gassiness of the crop. On vet's recommendation, fed her normal food (layer pellets) soaked/softened in water. Also fed some chopped ppached egg. Continued with massage.
That seemed to do the trick.
In retrospect, I think the massage and oil probably helped move the blockage, which had been making her unable to absorb nutrients, hence the skinnyness and dandruff. She seems on the mend now.
What I would have done, now that I have been through it:
1) Isolate her, monitor poop as described. Feed oil-soaked bread, masage A LOT until crop is mostly empty.
2) Massage massage massage
3) Feed regular feed softened a lot with warm water. Some egg but mostly feed, lots of water.
I hope this helps. Please feel free to email if you have any questions!
