Preheat the oven to 450 degrees F. Stir together the cornstarch, sugar, cinnamon, nutmeg, and salt. Beat into the squash. Add the maple syrup, milk, and butter and mix. Stir in the beaten eggs. Pour into the pie shell. Bake for 15 minutes. Lower the heat to 325 degrees and continue baking for 40 minutes, or until a knife inserted 1 inch from the center comes out clean. Remove from the oven and allow to set for at least 10 minutes. Serve warm or cooled. Top with whipped cream, if desired.