1) Combine Cocoa, cornstarch and sugar substitute in a saucepan. Gradually add milk, stirring with a whisk until blended. Cook over medium heat for five minutes until mixture is thick, stirring constantly. Remove from heat. Add margarine and vanilla, stirring until margarine melts. Pour into a bowl and cover surface of pudding with plastic wrap; chill.

2) Cut pound cake into one inch cubes. Arrange half of cake cubes in a 3 quart trifle bowl, and brush with 2 tablespoons orange juice. Spoon half of cherry pie filling over cake cubes. Spread half of the chocolate pudding over cherry pie filling. Top with half of whipped topping. Repeat layers with remaining cake cubes, liqueur, cherry pie filling, chocolate pudding, and whipped topping. Cover and refrigerate at least 8 hours. Garnish with fresh cherries and chocolate curls, if desired (I used the cherries, but not the chocolate curls).