Preheat oven to 375. Coat a 2-quart baking dish or 9-inch pie pan with cooking spray. Set aside.
In a large pot, combine frozen peaches, cornstarch, 1/3 cup brown sugar, and water. Cook over medium-high heat until peach are thawed and sauce is thickened, stirring often, about 8 minutes. Add in 1/2 tsp cinnamon and cranberries, cooking until heated through, another minute or two.
While fruit is cooking, combine remaining ingredients in a medium bowl: flour, apple sauce, 1/3 cup sugar, melted butter, and 1/2 tsp cinnamon.
Pour fruit mixture to prepared pan. Pour topping mixture over fruit, smoothing with a spoon to distribute evenly.
Bake for 25-35 minutes, checking the topping with a toothpick until it comes out clean.