I know it can get stressful---If you get attached and got kids watching too!
 
Let me tell you what I do----when I light and put the good eggs in the hatcher on day 18---I close the door--It will not be open again till day 22 Unless all the eggs hatch before then. Sure I look in the window a few times during that Lock-Down time---sure sometimes I see a pipped egg that is not getting any larger after 24 hours, sure I might see a chick having a problem some times, legs not right, egg shell stuck to it etc---I am sorry but I will not risk all the rest by opening it to help this one. Most of the time the problem corrects itself. If it goes to day 22 I open and remove all hatched chicks, If I have one or two that have pipped, still alive, sure I help them out the shell---wash off any that needs it and I also leave those in the incubator for another day. They come out the next day and the incubator/hatcher is cleaned for the next batch. If I have to Cull one---I hate it but You have to do what you have to do!