Drain pineapple, reserving liquid in 1-quart liquid measuring cup. Remove 1 tablespoons of the crushed pineapple, set aside for garnish. Add enough cold water to the reserved liquid to measure 3 cups; pour into large saucepan. Bring to boil; remove from heat. Add gelatin; stir at least 2 minute until completely dissolved. Add cranberry sauce; stir (gelatin mixture should be thick. Pour into large bowl.
Refrigerate 1-1/2 hours or until slightly thickened (consistency of unbeaten egg whites).
Stir in remaining pineapple, apples and walnuts; stir gently. Pour into medium serving bowl.
Refrigerate 4 hours or until firm. Top with reserved crushed pineapple just before serving. Store leftover gelatin in refrigerator.
Cooking time would actually be refrigeration time.