You know, I didn't add any water at all the whole time this time! The humidity went up and down by itself, from 30-45%. I calibrated my Hygrometer and it was 11% below, so I just kept an eye on it. Obviously if it goes down to 25% you have to add some warm water, but I think anywhere from 30-50% is fine! But then again I prefer a dry hatch. I haven't had any problems but with 1 baby with shrink wrapping. Everyone hatched good, although my numbers weren't high due to the breed of chicken and fragile eggs.
On lockdown, you just add more water or some people will put a wet sponge or washcloth in. I just added more water and got it up around 65% then once the babies start hatching, it stays up by itself from the moisture of the babies. Just keep an eye on it and if it needs to go up, just add some warm water. But for now, I think what you are doing is fine. If you get a minute, go up to the search and type in Dry Hatch, there is some good advice there and there are several people who add the water, let it go down, then add more. The fan won't effect the humidity, it just keeps the air flowing and prevents hot spots and cool spots.
Sounds like you are doing everything perfect, but I would try to get the temp between 99.5 and 100.5 (the 100.6 is fine) if you can...sometimes all it takes it a tap on the dial and it will be just enough. I have an LG and it is so touchy..once I get it set, I do not touch that bad boy...lol!