Good info to know. I had one I had to assist once that was still attached, so I set it back to rest. It's wiggling around detached it, but died right after. I didn't see anything pulled out, but perhaps pulled enough to cause internal damage? There was some blood, not a lot.Yes, that looks normal. Is the chick still connected? It should dry up and disconnect, but sometimes I very carefully snip those connections with disinfected scissors to ensure that the shell can't pull anything back out of the chick's navel (like if the chick gets the shell hung up on something and pulls).
If the navel isn't completely closed, a dab of pain reliever-free antibiotic ointment on it may help.
Congratulations on your hatchlings!