Get a pillow case and soak it in warm water for a few minutes. When it's fully saturated ring it out to where it's just damp. Put the snake into the pillow case and tie a knot in it. Place the snake (inside the pillow case) into her enclosure and leave her there for an hour or so. See if that helps to remove the remaining shed. Here are some threads that may help explain it better http://ball-pythons.net/forums/searc...earchid=965716

As far as keeping up the humidity in a tank...is the top a screen? Have you tried covering most of it with plastic wrap or foil? You can also mist daily to try and keep the humidity up. With a tank, it can really be a struggle to maintain appropriate humidity but people manage. Do some more poking around on this site and I'm sure you'll find more info on it as it's a pretty common issue.