Microwave the bag of potatoes for 6 minutes, then cut potatoes in half or quarters, depending on the size.
Add the corn, lemon, potatoes, sausage, butter and thyme to a large bowl. Toss together and place everything on the sheet pan with the corn standing on end and the sausage pieces sliced-side down.
Preheat oven to 400 degrees F.
Make a pouch using 2 sheets of aluminum foil, sealing the edges very well. Place the shrimp in the pouch and add the seafood seasoning. Add the beer and close the pouch. Place the pouch on the sheet pan, atop the sausage and vegetables. Place the sheet pan in the oven and roast until the potatoes are soft and the sausage is sizzling, 35 to 45 minutes. Remove from the oven and carefully open the shrimp pouch. Pour the pouch over the sheet pan and serve.