Bring a large pot of lightly salted water to a boil. Add macaroni and cook for 8 to 10 minutes or until al dente; drain, and rinse with cold water until chilled. Drain well.

Place the macaroni in a large bowl, and toss together with the bell pepper, onion, carrot, pineapple, reserved pineapple juice, and cabbage. Sprinkle with garlic powder, and toss to combine; set aside.

In a small bowl, stir together the Dijon mustard, vinegar, oil, white pepper, sugar, and yogurt; season to taste with salt and pepper. Toss the macaroni salad with the dressing, cover, and refrigerate for 1 hour to overnight.

To serve, toss the salad again to mix, then pour into a serving bowl. Sprinkle with coconut, and garnish with maraschino cherries.