
I agree that wiping it down with a slightly damp cloth will not harm a good humidor. It can cause warpage in the cheapies that use cedar plywood.
Heartfelt beads are the way to go for Rh maintenance. They are like magic and will last for many years. I think most use 65% beads and keep Rh between 62 and 65%.
Be sure to take some pics as you fill that baby up!