When I do one I think I would line the walls and ceiling in either tongue and groove boards or there is a similar plywood like product home depot sells. I think it is M11? Not positive the name off the top of my head. Either should hold up to moisture well. I think you should be able to hit the wall with a good sealer like drylock and just nail or screw into the studs. I would think that some of that wire shelving would work fine or if you got skills just make up some nice hardwood shelves. I think you also want somebcirculation fans. Maybe a small dict down low with an inline fan that moves it up to the ceiling and exhausts. Keep the moisture moving and stabilized. Some of the room humidifiers have a humidity sensor and I think that with the air movement would get the job done.