Heat coals or gas grill for direct heat. Cut 18 inch square of heavy-duty foil; spray with cooking spray.
Arrange scallops, fish and shrimp on foil, placing shrimp on top.
Sprinkle with marjoram, lemon peel and white pepper. Drizzle with butter and lemon juice.
Bring corners of foil up to center and seal loosely. Slide foil packet onto cookie sheet and carry to grill. Slide foil packet onto grill.
Cover and grill over medium heat 8 to 10 minutes or until scallops are white, fish flakes easily with fork and shrimp are pink and firm.
Meanwhile, cook and drain pasta as directed on package. Serve seafood mixture over pasta.