MIX juice and tapioca in medium bowl. Let stand 5 minutes. Meanwhile, melt butter in large saucepan on medium heat. Add pineapple, brown sugar, nutmeg and salt; mix well. Cook 5 minutes, stirring frequently.
ADD tapioca mixture; stir. Bring to a full boil , stirring constantly. Remove from heat. Cool 20 minutes. Transfer to serving bowl. Cover and refrigerate several hours or until chilled.
SPREAD whipped topping over pudding just before serving; sprinkle with coconut.