Beat the margarine, sugar and molasses in a large mixing bowl. Add egg and mix well. Sift together flour, baking powder, baking soda, cinnamon, cloves, ginger and nutmeg. Add to butter mixture; mix well.  Divide dough into 4 equal portions on a large piece of plastic wrap. Wrap and shape into a flat disk about 1 inch thick. Refrigerate until firm, about 8 hours, or freeze for 2 hours. (Dough can be refrigerated up to 3 days.) Heat oven to 350ºF.  Working with 1 disk of the dough at a time, roll out on a well-floured board, dusting the rolling pin as you work. Dough will be very soft and can be difficult to work with so work quickly and use plenty of flour. Using cookie cutters dipped in flour, cut into desired shapes. Put cookies 1 inch apart on an ungreased cookie sheet. Use currants or candy for eyes or buttons, if desired. Bake until lightly puffed, 7 to 10 minutes. First batch may be puffier because they will have less flour rolled in them. While still warm, paint with egg yolk wash if desired. Cool on wire racks. Cool completely, then decorate as desired with icing. Icing: Mix confectioners sugar with a small amount of water until thick and spreading consistency. Add food coloring if desired and put in a small plastic bag. Cut a small hole in one corner and drizzle icing out onto the cooled cookies.