Preheat oven to 350ºF. Grease a 9 x 5-inch loaf pan. Mix together carbquik, splenda, baking powder, pumpkin spice and baking soda in a medium mixing bowl. Stir in orange peel, shortening and egg. Add pumpkin. Mix until well blended. Stir in cranberries and nuts. Spread evenly in loaf pan. Bake for 55 minutes or until a toothpick inserted in the center comes out clean. Cool on a rack for 15 minutes. Remove from pan; cool completely. Wrap and store overnight. Makes 1 loaf (16 slices).