I think your humidity is fine. I keep my Royals at around 55% except when they're in shed when I whack them up. I use one of these misters you get for spraying plants and spray morning and night. One of my Royals is a Rescue who had problems shedding and was half-starved due to neglect. He shed yesterday and did it all by himself, every bit off in one piece from nose to tail, including eyecaps. I'll be putting a pic of him in the pictures forum shortly.

Royals (BPs) don't need so much humidity as some other snakes.