I know this has been largely resolved but in case anyone else comes wondering... I was always told to treat your snakes' enclosures as though it were a newborn baby's diaper. You wouldn't leave poop in your newborn's diaper, you would change it as soon as you noticed it. I was taught to treat snake enclosures the same way. If you remove waste and soiled bedding the second you notice it, it doesn't have time to grow bacteria or produce mold. Humidity is good for most snakes, it keeps them healthy and active and helps them shed cleanly. The only time humidity and moisture are a problem is when the enclosure is dirty, that is when mold appears.