I posted the problem in the on-line Bee Master forum. Many good responses also dealing with moisture. Then finally one beek mentioned that new wooden ware may sprout mold if the bees have not properly sealed the surface with propolis/wax.
BOOM! There it was!
When I thought about it all the wooden ware that came down with the mold was new. So I need to make sure all the wood is treated by the bees or someone else. Like me.
The current victim is the telescoping cover on Mary. It's a year old but the bees never waxed it. So I took it upon myself to wax it.
First I washed off the mold with bleach then dried it. Then warmed up the wood underside under a lamp. While that was happening I melted some bees wax & got a metal scraper. When all was ready I removed the lamp and poured the wax onto the T-cover. To keep the wax soft as I spread it I used a blow-drier. I did not coat to the edge of the T-cover. I feel that exposed wax may attract Wax Moths. After a good coating I put the T-cover back under the lamp to help the wax melt in. When completed the T-cover went back out on the hive.
I remembered Michael Bush's article on how he wax dips his hives. So I got the idea to hot wax the inside of my previously painted equipment. If this works (no more mold & no added pests like Wax Moth) I'll be sure to do this in the future when the bees don't do it themselves. I imagine that a strong & healthy hive will have no problem with this task. Mary on the other hand has always limped a little.