I will be honest, I have no idea why I had luck with my 1st open egg hatching. 

 I also had zero clue what I was doing & pretty sure I did all the things you’re not suppose to do. 

The eggs I used were in the refrigerator for almost 2 weeks. I put them in the incubator (99.5°-100°) for almost 72 hours before using a Dremel tool to cut the window. Then covered the top with the clear wound sheets I mentioned earlier.
I candled a LOT. 

 I also would cut the clear off to get photos & videos. Then I replaced the cover with a new 1. That’s what I did. Started 3, hatched 3. They’re 9 months old now.
The ones I started 14 days ago (4 ended up being fertilized), I’m down to just 1. Yolk still looks worrisome but it’s still going. If still good in 2 days (day 16) I will put it on lockdown since it’s a little bantam. How is yours doing?
Here is a video from tonight. It’s shaky because I use a magnifier app & screen record it while also holding a flashlight. 
EDIT: This chickie looks to have fused toes.