In food processor, place ricotta cheese, cream cheese and brown sugar. Cover; process until smooth. Refrigerate 10 minutes.
Spoon 3 tablespoons cheese mixture in center of each crepe. Fold sides and ends of crepe over filling to form a rectangle.
In 12-inch nonstick skillet, melt 1 tablespoon of the butter over medium heat. Add 5 blintzes, seam sides down, to skillet; cook 1 to 2 minutes, turning once, until golden brown. Remove from skillet to serving platter; cover to keep warm. Repeat with remaining 1 tablespoon butter and remaining 5 blintzes.
Meanwhile, microwave apples as directed on package. Stir in raisins. Spoon apple mixture evenly over blintzes. Top each with dollop of whipped topping; sprinkle with walnuts and powdered sugar.