I am getting things bit by bit. I found this site -tuXfiles - useful for explaining the basic file manipulation commands and how to use them.
I have used a combination of the graphical file manager and the command line to make copies of the file I am trying to replace. I have gone into SUDO super-user mode and replaced the old file with my edited version.

.....time passes....

I finally got things to work.
I can read a directory on the Linux box using the Windows computer.
Not exactly sure which of the changes I made did the job - I may look in daylight. Also not sure about the security of the changes, but it'll do for now.
Quack!
GtD.