Spray a 9x9x2-inch baking pan with cooking spray. Sprinkle with 3/4 cup of the crushed graham crackers or vanilla wafers. Set aside.
Drain pineapple, reserving juice. Add enough water to juice to equal 1/2 cup. In a small heavy saucepan, bring juice mixture to boiling. Add sugar and gelatin; stir to dissolve.
Gradually stir half of the hot mixture into the egg product. Return all to saucepan. Cook and stir for 2 minutes; do not boil. Remove from heat.
Stir in drained pineapple. Cover and chill until partially set (the consistency of unbeaten egg whites).
In a medium bowl, combine topping mix and milk. Beat with an electric mixer on high speed about 4 minutes or until stiff peaks form (tips stand straight).
Fold pineapple mixture into whipped topping. Spoon over crushed crackers or wafers in prepared pan. Sprinkle with remaining crushed crackers or wafers. Cover and chill in the refrigerator for at least 2 hours or until set. Makes 9 servings.