Preheat oven to 350 degrees. Cut squash cross-wise into rings. Discards seeds and pulp. Then cut squash rings and apple slices into 1 to 1 1/2-inch cubes.
Place in a 9 x 13-inch baking dish. Mix cinnamon with apple juice, and pour over squash and apples. Bake 15 minutes. Stir well, and bake another 15-20 minutes.
To serve, place about 1 cup of squash and apples in a bowl, and top with 1 tablespoon apple juice and 1 tablespoon walnuts.