Mix flour, oats and brown sugar in a bowl. Cut butter into pieces. Combine butter with the flour/oat mix, until the mixture resembles coarse meal.
2For the filling
Wash the cranberries and sort through, discarding berries that are mushy or white. Put cranberries into a pot with just enough water to cover, add sugar and heat through til boiling, about 10 minutes. Drain berries, combine in a large bowl with cherry pie mixture, orange peel and sugar.
3Butter a 13x9 glass baking dish. Pour fruit mixture into dish and crumble topping over fruit. Bake in a preheated oven at 350 degrees for 25-30 minutes or until the fruit is bubbly and the topping has browned.