Combine first 5 ingredients in a heavy saucepan. Cook over medium-low heat, stirring constantly with a wire whisk, 12 to 15 minutes or until mixture reaches 160° and is slightly thickened. Remove from heat; divide mixture in half. Let cool 15 minutes.
Add chocolate wafer crumbs, almonds, and coconut to half of butter mixture, stirring well. Press chocolate mixture firmly into an ungreased 9" square pan.
Add graham cracker crumbs, crushed amaretti cookies, and chocolate mini-morsels to remaining mixture, stirring well. Press graham cracker mixture firmly over chocolate mixture in pan.
Beat 1/4 cup butter at medium speed of an electric mixer until creamy; gradually add powdered sugar, beating until blended. Add milk and almond extract; beat until mixture is spreading consistency. Spread frosting over graham cracker layer. Cover and chill. Cut into 20 bars.
Spoon melted chocolate into a zip-top plastic bag. Snip a tiny hole in one corner of bag, using scissors. Drizzle chocolate over frosted bars. Top each bar with an amarettini cookie.