I have nailed and glued my bottom board on. I will set my tbh on a pallet so any rot will be there.
The interior of my hive is unfinished.
I myself haven't settled on the upper ventilation question. A 3/4 hole could be drilled and then plugged later with a piece of wooden dowel if not needed. In my standard equipment, I seasonally plug the vent holes with small pieces of pantyhose.
Let us know how your ventilation works out.
It's my first year with a tbh also.