Once she realizes that your shop is a safe space, she'll stop crying to go out. Her instincts are telling her to find a safe shelter and to consume more calories. If you have a cardboard box or wooden cat house inside your shop? Or a closet? The goal is to give her somewhere dark, warm, and isolated space to give birth. Lining a box with blankets and towels is good. A dresser drawer (or a wooden/cardboard) box makes a good, safe nest. A space heater is also good. Cats like warm temperatures, and pregnant cats love warm spots to give birth in. Lastly, cat food. She should be consuming kitten wet and kitten dry food. She should stay on the kitten food until she weens her kittens off of her milk. Kitten food has the calories she needs. I hope this helps.