I can tell you how to clean the musty smell, I would guess that you could take some black paint--I don't know if they used oil base or acrylic base, so you might like to look into it. I guess oil base is always safe.
The inside I would think would be pretty much the same touch it up with an oil base paint and let it dry well. A tip I have heard is to never pick up your case by the handle. Carry your case like you would a wooden box. I think it is made of plywood, covered with? My machine came without a box! You can buy a new box for about $50 from Nova Montgomery.