Allow eggs to stand at room temperature for 30 minutes. Meanwhile, lightly coat a 15x10x1-inch baking pan with nonstick spray for baking. Line the bottom of the pan with waxed paper or parchment paper; coat with nonstick spray for baking. Set pan aside. In a small bowl, stir together flour, baking powder, pumpkin pie spice, and salt; set aside.
Preheat oven to 375°F. In a large bowl, beat eggs with an electric mixer on high speed for 5 minutes. Gradually add granulated sugar, beating until well mixed. Stir in pumpkin and molasses. Fold in flour mixture. Spread batter evenly into prepared pan.
Bake about 15 minutes or until top springs back when lightly touched. Immediately loosen edges of cake from pan and turn cake out onto a towel sprinkled generously with powdered sugar. Slowly peel off waxed paper. Starting from a short side, roll up towel and cake into a spiral. Cool on a wire rack for 1 hour.
Meanwhile, prepare pumpkin cream filling: In a medium bowl, combine pumpkin and ground ginger. Fold in thawed whipped topping.
Unroll cake; remove towel. Spread cake with the filling to within 1 inch of edges. Roll up cake and filling into a spiral. Trim ends. Cover and chill for 2 to 48 hours before serving. To serve, place cake roll on a platter. If desired, garnish with rosemary sprigs and cranberries and sprinkle top with powdered sugar.
Tips: Sugar Substitutes: Choose Splenda® Sugar Blend for Baking. Follow package directions to use product amount equivalent to ½ cup sugar. PER SERVING WITH SUGAR SUBSTITUTE: same as below, except 153 cal., 27 g carb.
To make ahead: Prepare as directed; cover and refrigerate for up to 48 hours.