ok, for the humidity. the ambient humidity does not need to be high. instead try giving it a humid hide with moist moss or paper towels inside it.

it is tooo cold for that snake  might be why it's not feeding. ambient temps should be mid 80's cool side mid to high 70s. and a hot spot of 90-belly heat.

soaking will help with this shed but if you can keep a nice humid hide they will usually use that and regulate things themselves.... 

+1 to Silvia.

The heat tape on the belly is very important. you can also, intead of foil, use a humid towell ton the sreen top so it can keep moist inside, and screen the temp and hummidity until you get to the desired point. Try not to leave the old shed for to long, give him/her a bath and  help to take it out. Screen top  tanks are very hard to  regulate.   i bought  a fish tank light top and put it on top, it help me a lot, and it kept it very nice and warm.

+1 Sylvia. Also, feeding tongs are great because you can use them to do the "mousie dance". If that doesn't work, they also come in handy for removing corpses before they become icky. A humid hide and a bump in temps should solve the feeding issue and a nice long soak should help the shed issue. 

A lot of what you read about the "ideal" conditions for keeping some species are just that, ideal. Impossible to mimic outside of nature but ideal anyway. Sounds to me like you are doing all the right stuff and just need to tweak a few details.

I wouldn't worry if it's only the second feeding she refused. I think you might need some more hides and/or plants in there so she feels more secure. To increase humidity, I make sure my bedding is moist. Not just the top layer. When I clean my tubs, I dump the water right onto my cypress mulch. This keeps it from drying out. I'll also poor water on the cypress in between cleanings because my house has baseboard heat and it drys the air like none other. 

I also agree with the belly heat at 90ish degrees. They like it warm!! I wouldn't worry too much about the shed unless 2 or more bad shed build up. Usually if you can get the humidity up, you can get full sheds.

And I also want to point out how vauge 'misting' can be. I know what I thought misting was until I saw people with arboreals mist. There is quite a range. I've noticed a big differnce in spray bottle misting vs pump bottle misting vs misting systems. Those go from light to heavy mistings. Misting systems can be set to go for over a minute each time. Not that you're doing it wrong, just wanted to point it out.

Feed it an appropriate sized prey item.  Try an adult mouse, not a fuzzy.  You want the prey item to be at least as big around as the snake, and even hatchling ball pythons are much bigger than fuzzies.  Snakes are very vulnerable when they eat, using their only method of defense (their mouths) to do the eating.  So, when they do decide to eat, it's gotta be something big enough to be worth the time to be vulnerable.  For a ball python, that's a mouse or rat that seems aaaalmost too big for them to eat. 

+1 for all the comments to provide belly heat, the snake also sounds like she might be a little chilly.

Thank you everyone for the quick and helpful responses. I am going to attempt to change a few things around in the tank and see if I can't better maintain humidity and temperatures. What I am going to do:

Going to get a UTH.
Going to get a second digital thermometer for the warm side of the tank.
Going to get a humidifier for my room, it is arizona after all and is kind of dry here and the humidifier would not only benefit the snake but me as well.
Get some things to sort of 'clutter' the tank a little like fake foliage.
Going to look into feeding bigger prey. I had been using fuzzies because it was suggested not only by the pet store but also by another forum that I am on that fuzzies were fine after a size comparison picture was posted.

I do appreciate the advice I have been given and hope I have interpereted the information correctly and that the steps I am taking are appropriate.

~KayDee