Cream margarine and sugar until smooth. Add molasses and eggs. Beat until smooth. Add baking soda, salt and spices. Gradually beat into the sugar mixture the flour, beating until just mixed. Put in enough so the dough will be heavy and stiff. Preheat oven 350 degrees. Put parchment paper on your baking sheets. Roll out dough on a floured surface about 1/8-inch thickness, DO NOT MAKE THICKER. Place the pattern piece on the rolled dough and cut neatly around edges with a sharp knife. Carefully remove scraps and press into a ball: reserve scraps and continue rolling and cutting until all 6 pieces are done. Bake for 15 minutes, NO Longer Bake pieces 10-15 minutes, until edges are lightly browned. Carefully remove baked pieces from sheet and placed on cooling rack. Let the pieces dry out. When ready to assemble in mixer add powder sugar together with egg whites, add just enough egg whites that the frosting is stiff. Fill a ziplock bag squeeze down to a corner and twist. Cut corner and squeeze so the frosting pipes on the side edges and bottom of the two sides and two ends. Place on base and put corners together. The sides need to be inside the corners of the ends for the roof to fit correctly.