Chicks pipping but not zipping and squished feet

[SpotTheCat]

I have had about 7 out of 20 coturnix chicks managing to pip but they have not zipped (at least 12 hours later) temperature may have been low, humidity has been about 30% and 50-60% at lock down

Most of the chicks I have hatched from one pair of quail have squished feet other quail that were incubated with them had normal feet, the pair may be siblings could it be inbreeding?

 

[SpotTheCat]

the incubator
its my first time using it, not my first time incubating

 

[SpotTheCat]

I have had two with kinked necks and deformed beaks that I had to help out of the egg, one of them has died. One of the normal chicks died and another one is very weak and looks like it might die, no idea why