How about this: The grow closet is in my bedroom which is in the basement. The whole house has central AC. If I keep the door to my closet open, and the door to my bedroom closed the AC should regulate the temp in the bedroom and the fresh air can be directed into the closet via a couple strategic fans!
For multiple reasons I cannot drill, cut or blast holes in the ceiling...
Edit: When flowering time comes, 12hr on / 12 off should be a "short" enough time to keep the closet door closed to exclude bedroom light. Also maybe the added heat will produce more resin?