It's fine if they bump the other eggs. It will only make the chicks hatch faster and I often purposely leave 1 or 2 in the bator after I remove the first hatchers so they will knock the eggs around and peep. It makes the hatch go twice as fast. The only time it's a danger is if the humidity is too high because then if a pip gets turned down the excess water collecting in the egg will run into the chicks beak. If your numbers are right then there's no risk. I probably remove mine about every 12hours depending. If I'm having major humidity issues or something and I don't have many eggs so it isn't too crowded I may leave them 2 days before removing any.
You should read the same humidity throughout the bator. It's the temp that will have large differences depending where you put the thermometer especially in a still air. If you need a real quick humidity boost you can toss in a wet paper towel or rag real quick. Did you test your humidity gauge before using it? Most are inaccurate and need to be tested by leaving it in a bag of wet salt for a day and checking what it reads. Otherwise assume it's at least a few and possibly up to 10% off.
