I, too, pre-booked space for playing games and LCR and was given the port conference room on deck 3 outside the dining room. If you go past the stairs on that side and enter the cabin corridor, you just turn left and enter that door. It is actually part of the dining room at night so they ask us just to keep it neat and put glasses etc on the serving station as one of the wait staff comes after you leave to reconfigure it for dinner.