Preheat oven to 350°F (175°C).

In a large bowl, blend together cake mix, coconut, and softened margarine until crumbly.

Press the mixture into the bottom and up the sides of a 13 x 9-inch pan.

Spread apple pie filling evenly over the crust.

In a separate bowl, mix sugar and cinnamon together.

Sprinkle the sugar and cinnamon mixture evenly over the apple pie filling.

In another bowl, blend sour cream and beaten egg together until smooth.

Spoon the sour cream mixture evenly over the top of the apple pie filling.

Bake in the preheated oven for 25 to 35 minutes, or until the topping is set and lightly golden brown.

Let cool slightly before serving.