A basement is a cube, if 4 sides and the floor is insulated the heat will rise, and go to cold. Insulated walls will block the circulation, room to room fans may help move the heat. The floor above the stove will be warm as long as there isn't insulation there. A stairwell may help with return air as well as heat movement. There are many variables here and many questions. What kind of stove or furnace or boiler is a keystoker 85000?