My mojo Morris just shed Friday night, he ate thursday afternoon and still did nicely. My female spider on the other hand was having the same issue as Pedro. I just got done soaking her and getting all of that stuck shed off. I can definantly sympathize.
I can't imagine it being a humidity issue. There are three fish tanks totaling 260 gallons that keep the living room of this apartment at 60% humidity at the lowest. The snake tubs usually stay between 65-68%. When I checked in on my spider the humidity was sitting at 72%, I am thinking that maybe that moss idea may be a big help.