Preheat oven to 350°. Line two greased 9-in. round baking pans with waxed paper; grease paper and set aside.
In a large bowl, cream shortening and sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in melted chips and vanilla. Combine flour, baking powder and soda; add to creamed mixture alternately with buttermilk, beating well after each addition. Transfer to prepared pans.
Bake 26-30 minutes or until a toothpick inserted in the center comes out clean. Cool 10 minutes before removing from pans to wire racks to cool completely; gently peel off waxed paper.
In a small saucepan, bring raspberries and water to a boil. Reduce heat; simmer 5 minutes. Remove from heat. Press raspberries through a sieve; discard seeds. Cool.
In same pan, combine sugar and cornstarch; stir in raspberry puree until smooth. Bring to a boil; cook and stir for 2 minutes or until thickened. Cool. Spread between cake layers.
In a large bowl, beat cream cheese until fluffy. Beat in melted chips; fold in whipped topping. Spread over top and sides of cake. Pipe frosting over top edge of cake and garnish with berries if desired. Store in the refrigerator.