If it was my chick, I would be inclined to give her free-choice access to: grit, chick starter, plain water (all in separate dishes.) Since massaging her crop seems to make her feel better, I would continue with that as well.
If you've been withholding chick starter, and she's getting weak, I would worry that she's just plain not getting enough to eat!
You say she likes to eat chick starter and grit, and she is pooping. So I wonder if she'll get better faster if you just leave her to it, and quit giving her a bunch of odd things.
(I am not a vet, nor an expert, so take my opinion with a grain of salt.)
If you've been withholding chick starter, and she's getting weak, I would worry that she's just plain not getting enough to eat!
You say she likes to eat chick starter and grit, and she is pooping. So I wonder if she'll get better faster if you just leave her to it, and quit giving her a bunch of odd things.
(I am not a vet, nor an expert, so take my opinion with a grain of salt.)