1. Preheat oven to 350°.
2. Wrap potatoes in aluminum foil. Bake potatoes at 350° for 1 1/2 hours or until tender, and discard foil. Let stand 10 minutes; peel. Place flesh in a large bowl; discard skins. Mash flesh with fork. Stir in fat-free milk, 1/4 cup sweetened condensed milk, sugar, butter, 1/2 teaspoon cinnamon, vanilla, and salt. Stir in eggs.
3. Fit dough into a 9 1/2-inch pie plate coated with cooking spray. Press dough against bottom and sides of pan. Fold edges under, and flute. Spoon sweet potato mixture into prepared crust. Bake at 350° for 45 minutes or until set.
4. Place the remaining 1/4 teaspoon cinnamon and cream cheese in a medium bowl. Beat with an electric mixer until combined. Add 1/2 cup plus 2 tablespoons sweetened condensed milk to cheese mixture; reserve remaining milk for another use. Beat at medium speed until well blended. Carefully pour cream mixture evenly over pie. Let stand 10 minutes. Cut into wedges.