Dissolve jello in boiling water in medium bowl. Stir to dissolve. Drain pineapple, reserving juice, and set fruit aside. Stir pineapple juice, lemon juice, and lemon zest into jello mixture. Chill 'til just set (about one hour) Stir in Cranberry sauce, raspberries, crushed pineapple, and walnuts. Pour into 4 1/2 C. ring mold sprayed with vegatable oil or lightly greased. Chill at least 4 hours or over night. Unmold and garnish edges of salad with lemon slices alternating fresh cranberries.