Thank you Steve; you have expanded my knowledge of Audacity.
I used your code then modified it (I am a programmer after all!):-
Comment:_="ConcatenateFiles"
Comment:_="Entry: The set of files has been loaded in the required sequence (File, Import,Audio)"
Comment:_="Exit: The assembled file will be found in the folder 'macro-output' within your project folders (Edit, Preferences, Directories)"
Comment:_="Thanks to steve https://forum.audacityteam.org/t/concatenating-tracks/64088/2
Comment:_=""
SelectAll:
Align_EndToEnd:
ExportWav:
Comment:_="ConcatenateFiles END"
I have set myself a schedule of making one macro a day, each day I write a macro with a “new” command.
My theory is that this will introduce me to each of the commands at a manageable rate.
Today you have propelled me forwards by two days! 
Thanks again
Chris