MIX jelly powder and water in medium microwavable bowl. Microwave on HIGH 1-1/2 min.; stir until jelly powder is completely dissolved.
SET aside 12 of the marshmallows. Add remaining marshmallows to jelly; stir until well blended. Microwave on HIGH 1 min. or until marshmallows are partially melted. Stir with wire whisk until marshmallows are completely melted. Pour into 9-in. square pan sprayed with no stick cooking spray.
REFRIGERATE 45 min. or until set. Run sharp knife around edges of pan to loosen jelly layer from pan. Starting at 1 edge, roll up jelly layer tightly. Cut into 12 (3/4-in.-thick) strips. Refrigerate, covered, until ready to decorate.
UNROLL each about 1 in. Stand 1 of the reserved marshmallows on unrolled portion of each spiral for the "snail's body," securing with frosting. Insert 2 pieces of licorice into each marshmallow for "antennae," securing with additional frosting, if needed.