Heat oven to 350 degrees. Pour melted margarine in 15 x 10 inch jelly roll pan. Sprinkle graham cracker crumbs over margarine, shaking pan to distribute crumbs evenly. Layer in coconut, candied fruit, dates and walnuts. Press mixture gently to level. Pour sweetened condensed milk evenly on top. Bake at 350 degrees for 25 to 30 minutes or until set and lightly browned. Cool in pan on wire rack. Cut into bars or squares.