Prepare the Strudel Pastry. Place the 15-inch circle in a 9x1-1/2-inch round baking pan so the dough hangs over the edges of the pan. Set aside.
In a bowl, beat together cream cheese, the 6 tablespoons water, the 3 tablespoons sugar, and the egg with an electric mixer on medium speed until smooth. Set aside.
In a large saucepan, combine the 3/4 cup sugar, the cornstarch, cinnamon, and salt. Stir in the 2 tablespoons water; add apples. Cook and stir gently over low heat until apples are transparent and mixture is slightly thick.
Spread the pastry in pan with half of the cream cheese mixture. Place an 8-1/2-inch circle of pastry on top. Spoon in all of the apple mixture, arranging slices evenly. Top with nuts.
Add the remaining pastry circle. Spread with remaining cream cheese mixture. Fold the overhanging pastry toward the center, pleating edges as necessary to partially cover cream cheese layer.
Bake in a 400 degree F oven for 15 minutes. Reduce heat to 375 degrees F and bake about 35 minutes more or until crust is golden. Remove from oven. Sprinkle top with additional sugar.
Cut into wedges. Serve warm. Makes 10 to 12 servings.