Drain pineapple, reserving juice.

In large bowl, stir together pineapple chunks and marshmallows; cover and chill for up to 24 hours.

For dressing, in a small saucepan stir together the sugar, flour, reserved pineapple juice, vinegar, and egg.

Cook and stir over medium heat, just until mixture bubbles.

Reduce heat; cook and stir for 2 minutes more.

Transfer the mixture to a small bowl.

Cover and chill.

To serve, add chilled dressing and apples, cool whip, cherries, and peanuts to marshmallow mixture; stir to mix well.