Microwave butter on high until melted; stir until smooth. Stir in cookie crumbs, coconut and cream of coconut until blended (mixture will be wet). Spread onto bottom of an ungreased 13x9-in. baking pan. Refrigerate until set, about 30 minutes., For filling, beat butter, cream of coconut and extract until smooth. Gradually beat in confectioners' sugar and enough milk to reach a spreading consistency. Spread over crust., For topping, microwave chocolate chips and oil until melted; stir until smooth. Cool slightly; spread over filling. If desired, sprinkle with chopped candy bars. Refrigerate.