In a mixing bowl, combine milk, shortening, granulated sugar and salt. Soften yeast in warm water. Add to milk mixture. Add egg. Stir in flour to make a soft dough. Turn onto lightly floured board. Knead lightly until smooth. Grease 13-by-9 1/2-by 2-inch baking pan. Roll out dough into rectangle. Brush with melted butter. Combine brown sugar and cinnamon. Sprinkle dough with brown sugar mixture and raisins, if desired. Roll up lengthwise like a jellyroll. Cut into thick slices, about 1 inch wide. Arrange in pan. Let rise for about 1 hour. Preheat oven to 350 degrees; bake for about 30 minutes. Upon removing from oven, spread immediately with the icing. Icing: Mix confectioners' sugar and vanilla with warm water to make a glaze.