Preheat the oven to 350 degrees F. In a mixing bowl, combine the butter, crumbs and brown sugar. Mix thoroughly. Press the crust on the bottom of a greased 8 inch by 8 inch by 2 inch square baking pan. Sprinkle the pecans over the crust. Sprinkle the chocolate chips over the pecans. Sprinkle the coconut over the chocolate chips. Sprinkle the butterscotch chips over the coconut. Pour the condensed milk evenly over the top of the chips. Place the pan in the oven and bake for 30 minutes. Remove the pan and cool completely. Slice into 8 equal pieces. Place one piece of the bar cookie on four individual plates. Place 2 scoops of ice cream on top of each bar cookie. Top the ice cream with the remaining cookie pieces. Drizzle with the chocolate sauce.