I think the day 4 egg looks about right.
I'm having trouble seeing quite where the air cell is in the other eggs, so I'm not sure about them. Even if it does not show up in the photo, you might be able to tell. Day 7 eggs are supposed to have a bit bigger air cell than day 4 eggs.
If the air cells are about right, then just keep doing what you have been doing for humidity, and check them again in a few days or a week
I'm having trouble seeing quite where the air cell is in the other eggs, so I'm not sure about them. Even if it does not show up in the photo, you might be able to tell. Day 7 eggs are supposed to have a bit bigger air cell than day 4 eggs.
If the air cells are about right, then just keep doing what you have been doing for humidity, and check them again in a few days or a week

That's so exciting! Welcome to BYC! I'm so excited to think people here are trying to help you hatch chickens on the other side of the planet from me, what fun! I wish you all kinds of luck, so please let us know how it goes for you. What kinds of chickens are you hatching?