In a bowl, mix oil, lemon juice, minced garlic, salt, and pepper.

Add shrimp to the mixture and ensure they are well coated.

Marinate the shrimp in the refrigerator for 15 minutes.

In a small saucepan, combine brown sugar, dark rum, corn syrup, Dijon mustard, butter, cinnamon, salt, and pepper.

Bring the sauce to a boil over medium heat, then reduce heat and simmer for 5 minutes, stirring occasionally.

Thread 4 marinated shrimp onto each skewer.

Preheat grill to medium-high heat and coat with cooking spray.

Place skewers on the preheated grill.

Cook for approximately 3 minutes per side, basting generously with the rum sauce during cooking.

Serve immediately.