Box,
After having changed the position of the surface from horizontal to vertical, and changed the path from pointing downwards at an angle of about 42° to 0°, I also used the Scale tool to increase the size of the whole thing by 100; this appeared to make the FollowMeAndKeep Extension do what I wanted. Then I used the Scale tool to take me back to the original size; all was good.
So, I have finally solved my problem and once again thank everyone for their help and suggestions.
johnmtb