Beat butter, egg yolk, lime rind, and juice in large bowl until smooth. On low, beat in confectioners' sugar, flour, and salt until blended. Refrigerate dough 1 hour or until firm.
Heat oven to 350 degree F.
Form 1 rounded teaspoon dough into 2-1/2-inch log; bend into crescent. Place on ungreased baking sheet. Repeat with remaining dough.
Bake in a 350 degree F oven 10 minutes or until edges are just golden and tops are slightly cracked. Let cool on baking sheet 5 minutes. Remove cookies to wire rack and let cool completely.
Stir together confectioners' sugar and lime juice in small bowl until smooth. Place wire rack with cookies over waxed paper. Decorate cookies with drizzle. Sprinkle with decorator sugar. Makes about 4 dozen crescents.