This does not work!
The error occurred with the opening tag on the function line (20) which looked like a curly brace, but it was NOT. Re-entering that character made it work!
I have many examples which I learned five years ago, but now I have forgotten. Previous work is located here. I shall return to this program later. I do not want to start mixing different references.
Here is another form of the reference: Folder in File Server
I was trying to reduce the size of the Index display, but could not find the way.