i helped my last one out since there were no others to be concerned about...not sure it was the right thing to do.  she never zipped, just chipped out a dime sized hole and then NOTHING.  it was awful to see her little beak/head in there, peeping.  i believe the3 air sac was somehow wrong.  
this was a shipped egg and i had noted it seemed to be on the side of the egg and the end.  so it was interesting that she didn't zip as expected.  i left her in there from 12 am to 8 and i opened her egg a bit more this morning just to see.  she came out in the steamy bathroom and is now all alone in the bator.
she seems awfully weak and i am wondering if  being in that weird position for so long, with just a wing out, hurt her permanently,  hard to say right now.  she definitely needs time to strengthen, but she may have a curled foot too--the only one of all my 25 to have that, which i am glad of.
HATCH RECORD (my first!)
gqf hovabator (first hatch, new bator)
used egg turner
31 eggs went into lockdown 
25 hatched
non-hatchers 2 shipped (AAxEE), 4 of my own eggs: 1 java (pipped then died), 1 GLW (pipped then died), 1 EE, 1 Brown leghorn (both never pipped.  the blue one was iffy when i out it in for lockdown).
eggs into egg cartons with bottoms cut out for hatching.
incubation--dry (30-40%) in nw arkansas
hatch humidity--70-75% 
i feel this was a real success.