In a saucepan heat the soup to boiling point. In a bowl soften the gelatin in cold water and add to the soup. Stir to dissolve. Add the cream cheese in chunks. Beat with a rotary beater until smooth. Add 1/2-cup mayonnaise. Fold in the crab meat, celery and green onion. Spray a fancy mold with cooking spray and pour the mixture into the mold. Chill until set. Un-mold to serve.