Question: All of my puzzles disappeared from "My Puzzles"

Answer: The puzzles are associated with your computer by using web cookies. If you do anything that interferes with that association, then you won't be able to access your old puzzles. This includes moving to a new computer, using a different web browser, explicitly deleting cookies, running any of the privacy programs that deletes cookies, etc. We don't ask for any identifying information in order to set up an account; the cookie is the only thing that ties everything together.