Cook macaroni in salt water until tender, usually 11 minutes. Rinse in cold water. Drain well.
Drain pineapple, reserving 1 cup of juice.
Drain cherries and oranges.
Put fruit on top of macaroni and refrigerate.
In a sauce pan, mix the reserved pineapple juice, sugar, salt and flour. Beat all with a wire whisk until smooth. Cook until thick stirring continuously.
Pour mixture over macaroni and fruit. Mix well and refrigerate overnight.
Next morning fold in 8 oz cool whip.