sorry, I'm not a professional in the English language. What does the following must-requirement mean:
"You must not require manual editing of any files by the examiners."
I just don't understand what I have to do to fulfill this requirement?
You don't really have to do anything to meet this requirement.
It means: you just can't expect that the examiner has to change some file to point to your database file or to change the port number before running your application. So if your program runs without having to modify a file manually (and you show a dialog for example to let the examiner point to the database file and enter the port number), you're good to go.