Thaw pineapple juice and simmer until it is reduced to ½ c. (or until the total is ⅓ less). Cool.
Soften gelatin in water at least 5 minutes.
Add egg yolks to pineapple juice; add gelatin and ½ c. sugar. Place in double boiler. Cook 10 minutes, stirring often. Remove from heat. Add salt and orange peel. Mix well and chill until mixture thickens, but do not let it set. It usually takes about 45 minutes.
Beat egg whites until frothy, then gradually add ¼ c. sugar while continuing to beat. Beat until stiff peaks form. Fold in whipped cream. Fold egg white mixture into pineapple filling and spoon into cool pie shell.
At serving time, garnish, if desired, with 6 pineapple flowers. To make flower, arrange 5 drained pineapple tidbits around a maraschino cherry.