From what I read, it sounds like your main issue is humidity. The squeaky noise or however you described it is most likely from being too dry it can cause almost a whistle sound as they breath and the bad shed is an obvious indicator as well. It makes sense that it would be too dry with your setup, it is near impossible to keep good humidity with a screen top. I would recommend blocking most of the screen with plexiglass or something similar and leave just a small area for air exchange. Watch your temps after doing this because it will most likely keep the enclosure warmer as well because with an open screen top you are constantly losing warm air. Just keep an eye on it and adjust as necessary until you have your temps dialed in again. Then to keep your humidity up just add a little water to the substrate weekly or as needed. You do this and next shed will be perfect. The noise when breathing should clear up quickly as well. Good luck.