My brother in law designs sprinkler systems for large buildings. When he is done with the file he stores it in a cad library that his company has in place to keep all of its data secure for any type of future reference. I do not think that there has ever been any problem with an installation of the systems but if there ever was then because the files are saved they can go back and see what is wrong.
Are you a fan of the movie Spirited Away? This is a story of a 10-year-old girl and her parents. While traveling to their new home, his father made a wrong turn. They unknowingly entered into a magical world. Both of Chihiro's parents were turned into giant pigs. Chihiro met a mysterious person named Haku. He explained that the world her parents were into is a resort for supernatural beings and she must work there to free herself and her parents.