I was under the impression that bps only had scales on there bellys and that the rest of there body was a scale like skin... I'm guessing thats incorrect or somebody more knowledgable then myself would have said something.

As for humidity if you have a glass tank you could always try covering 3/4s of the cage lid. Or you could switch to a plastic tub. I maintain 65% humidity with just having my water bowl partially over the UTH, and thats in utah where the humidity over the last few days has been in the 10 to 20% range.

GL