They may be custom functions. Take a look in FIle>Manage>Custom Functions…
They are indeed custom functions specific to this file. If you do not have FileMaker Advanced, you will not have access to their design nor be able to move the functions into a different file.
Yes, that seems to be what they are. As I am just trying FM12 in the trial mode, I did not have access the the 'advanced' version. I have found everything I want, but those had me stumped.
Good to hear from you again Phil.