Combine 1/2 cup apple juice, 1 tablespoon olive oil, vinegar, mustard, thyme and Worcestershire sauce in a medium bowl. Stir well; add shrimp and peppers and stir to coat. Let stand at room temperature 5 minutes or refrigerate for 15 minutes.
Thread shrimp and peppers onto 4 skewers. Discard marinade. Grill or broil kabobs 4 to 6 inches from heat for 4 to 6 minutes. Turn kabobs and grill an additional 4 to 6 minutes or until shrimp are opaque.
Combine remaining apple juice, olive oil, contents of spice sack from commercial couscous and water in a medium saucepan. Bring to a boil; stir in couscous; cover; remove from heat. Let stand 5 minutes. Fluff lightly with a fork and spoon onto individual serving plates. Top each serving with a kabob.