Combine 1/2 cup apple juice, 1 tbsp olive oil, vinegar, mustard, thyme, and Worcestershire sauce in a medium bowl; stir well. Add shrimp and peppers; toss to coat. Let stand at room temperature 5 minutes to marinate.

Thread shrimp and peppers onto 4 (12 inch) skewers. Discard marinade. Grill or broil kebabs 4 to 6 inches from heat for 4 to 6 minutes. Turn kebabs, and grill an additional 4 to 6 minutes or until shrimp are opaque.

Meanwhile, combine remaining 1/2 cup apple juice, remaining 1 tbsp olive oil, contents of Spice Sack and water in a medium saucepan. Bring to a boil; stir in couscous. Cover; remove from heat. Let stand 5 minutes.

Fluff couscous lightly with a fork, and spoon onto individual serving plates. Top each serving with a kebab.