Look around the office. Take the shovel, pickaxe and bellows to be picked up later.
Look for Mona's grave on the graveyard map on the wall. Froderick finds it in A1 13.
Shrowdy appears and demands that Mona return to castle. He locks the 2 inside the office.

Escape from the locked office: Check the door and the window.
See an empty water basin under the downspout that collects water.
Snow covers the roof and the tree branches above the roof.
Increase the fire in the furnace by throwing perfume in the furnace. The increased heat melts the snow on the roof and the tree branches filling the water basin. The water in the basin freezes.
Use the shovel on the window to tilt the filled water basin. The ice falls in front the door.
Use the pickaxe on the door to increase more space on the base of the door.
Use the shovel in the furnace to make it red hot. Use the heated shovel on the door. It melts the ice and it pools on the floor of the office.
Use the bellow on the pool of water. Use the bellow with water on the furnace. The fire is put out.
The bats fly out of the office.