I think you should add at least one fan (I have 4 in my kiln) to ensure the air is well circulating, it helps the temperature and humidity to be the same everywhere in the kiln.
Even in well insulated kiln you can have condensation if your leaves are too close against the walls, let some place to allow the air to pass.
Even in well insulated kiln you can have condensation if your leaves are too close against the walls, let some place to allow the air to pass.