You added a fan in the room, or is it pulling air in from a cooler location?
Cross ventilation would help out with the heat.... pull cooler air in from another location, and allow it out of the grow area opposite of where it comes in.
You have 18 23watt cfl's in there.... all across the top? or on the sides and back as well?
Can you post a pic of how you have your lights set up for me? Looks like you have bathroom vanity light bars in there....?