Never tried a crockpot for deer roasts... The best way I know how to cook them is to cut up a garlic clove and poke it down into the roast in several places. Make a mixture of crushed bread crumbs, olive oil, garlic, salt and pepper into a paste and cover the top and sides of the roast with it. Cook it in the oven at 325 F for about 20 minutes per pound. Comes out nice and juicy.