I think it's best to let all the pipped ones hatch before you open the bater to help that one which has made no progress. Do you have other's already pipping too? If so, you put those at risk by opening the bator. I would wait a while until all pipped ones have hatched and dried, then when you remove them you can check on that one with no progress. Sometimes I feel that nature just doesn't want all of them to hatch for some reason. Remember they can live for 2-3 days easily in the incubator.
Sorry forgot to say it FINALLY came out! And its CRAZY!!! Had to go ahead and remove it from the bator cause it was stomping all over the others heads!! I hope I didn't kill the pipped one, but if I didn't, it woulda killed them probably. Lol. I did it SUPER quick! Surprised I didn't give it a heart attack I grabbed it so fast.