Preheat oven to 375 degrees F. Prepare Pastry for a Double-Crust Pie. On a lightly floured surface, use your hands to slightly flatten one pastry ball. Roll pastry from center to edges into a circle about 12 inches in diameter. Wrap pastry circle around the rolling pin. Unroll pastry into a 9-inch pie plate. Ease pastry into pie plate without stretching it.
In a large bowl stir together granulated sugar, flour, apple pie spice, salt, and ginger. Add apples and cranberries; toss gently to coat. Transfer apple mixture to pastry-lined pie plate. Trim pastry to 1/2 inch beyond edge of pie plate. Fold under extra pastry even with the plate's edge. If desired, crimp edge.
Roll the remaining pastry ball until 1/8 inch thick. Using a pizza cutter or a 1 1/2-inch leaf-shape cookie cutter, cut out leaves. If desired, make vein imprints on leaves with the tip of a table knife. Arrange pastry leaves on top of pie. Carefully brush leaves with milk and, if desired, sprinkle with coarse sugar.
Cover edge of pie loosely with foil. Place pie on middle oven rack. Line a baking sheet with foil; place on bottom rack to catch any drips. Bake for 30 minutes. Remove foil from pie. Bake for 40 to 50 minutes more or until apples are tender and filling is bubbly. Cool on a wire rack.
Pastry for a Double-Crust Pie
In a large bowl stir together flour and salt. Using a pastry blender, cut in shortening and butter until pieces are pea size. Sprinkle 1 tablespoon of the ice water over part of the flour mixture; toss gently with a fork. Push moistened pastry to the side of the bowl. Repeat moistening flour mixture, using 1 tablespoon of the ice water at a time, until all of the flour mixture is moistened. Gather flour mixture into a ball, kneading gently until it holds together. Divide pastry in half; form halves into balls.