As a newcomer to Filemaker, I was surprised to learn the project closes when the one & only layout in my project is closed down; particularly when I was trying to do some scripting without the Database or Layout pages open.
To overcome this I have stumbled on the notion of creating a dummy table and a dummy layout with the same name - that is a row of hyphens ("-")
This allows me to use the table name AND the layout name as a "separator" in both the Database and Layouts list.
Now - when I open the Filemaker application to work, I open the dummy layout ( which is completely blank ) and minimise the window.
This means I don't accidentally shut down Filemaker...
Yes, the table name and the layout name both contain illegal characters - however since neither are ever referenced in the application; I don't perceive any problem.