Spray inside of Crockpot with non-stick cooking spray.
Empty cans of Blackberry Pie Filling into bottom of Crockpot, and spread out evenly.
Scoop dollops of Cream Cheese on top and place on top of Blackberry Pie Filling.
In medium mixing bowl, combine dry Cake Mix and melted Butter, and stir until crumbly. (break up any large chunks into small crumbles with spoon or your fingers.)
Pour cake/butter crumble mixture over blackberry/cream cheese mixture in crockpot, spread out evenly, and cover crockpot with lid.