Slice apples into lemon juice and toss. Add cranberries and mix. Combine cinnamon, nutmeg, Splenda® and cornstarch. Sprinkle over fruit mixture and toss. Put into small casserole. In a small bowl combine brown sugar, oats, cinnamon. Cut in margarine. Add walnuts, and sprinkle over the top of the fruit.

Bake at 375º for about 30 minutes until fruit is tender and topping is slightly browned.