Fire up. Prepare a grill for high heat cooking, approximately 400°F (204.4°C).
Prep. Cut the potatoes in half. Cut each ear of corn crosswise into 8 even sections. Cut the smoked sausage into ½-inch (12.7 mm) slices. Remove the ends from the lemon and cut into ½-inch (12.7 mm) slices.
Combine the potatoes, corn, sausage, shrimp, olive oil, and 1 ½ tablespoons of the Old Bay seasoning in a large bowl and toss until evenly coated.
Place the seasoned ingredients in a disposable aluminum half pan. Add the lemon slices, butter, beer, and water. Sprinkle the remaining Old Bay over the ingredients, and cover the pan tightly with foil.
Cook. Place the aluminum pan on the grill and cover the grill.
Allow the packet to cook until the shrimp is cooked through and the potatoes are fork tender, approximately 25 minutes.
Remove the aluminum pan from the grill and carefully open the foil to allow the steam to escape.
Serve. Serve immediately in the pan or spread out on sheets of newspaper.