Q: Why are my hens pecking a hole in the top of their eggs? GRR

I can't figure it out. They are laying really good, but my best layer (GSL) is pecking a hole in the top of her egg, thus ruining the egg. My other girl who lays doesn't do it as much, in fact these last two days she hasn't pecked her egg at all, but has anyone else had their hens do this?
And another note on this is Poppy (GSL) is having a nest box crisis. She can't figure out where to lay. She has laid IN the nest box (the correct place) her first year, but we recently integrated two teenage chickadees and these to hens aren't used to more chickens around (I know, it's sad) are uncomfortable to lay in the nest box. Poppy has had misadventures jumping over our 7 ft high brick wall that separates our yard from a busy street, well she laid her egg in the bushes and was walking on the sidewalk looking around when I jumped over the wall and brought her back home. (what a sight I must've been holding a chicken in the heart of suburbia ) Anyways, what should I do? I've put golfballs in their nest box, that's how I got June (the other girl) to lay in the nest box, but what about Poppy? Where going to move soon, and when we do I don't want her to be under a lot of stress and never have a good nest box life again. Help!

WW