HEAT oven to 350ºF.
MIX pretzels, 1/4 cup sugar and margarine; press onto bottom of 13x9-inch pan. Bake 10 min. Cool.
BEAT cream cheese spread, remaining sugar and milk with mixer until well blended. Stir in Cool Whip with whisk; spread onto crust. Refrigerate until ready to use.
ADD boiling water to jelly powders in large bowl; stir 2 min. until completely dissolved. Stir in cold water. Refrigerate 1-1/2 hours or until thickened. Stir in strawberries; spoon over cream cheese layer. Refrigerate 3 hours or until firm.