Thanks Mark for the quick response
Opening the support files via the TBX app did indeed show the collection of subfolders ( config, favourites, fill etc...) However, I could not backtrack to their parents within finder which gave me a lightbulb moment of suspecting hidden folders. A quick google search led to;
if you need to access the ~/Library folder from within an application, you can make the folder permanently visible. Just open Terminal and type in:
chflags nohidden /Users/[username]/Library/
Replace [username] with your user name(!) and hit return. Then you can quit Terminal and your user Library folder will be visible.
This did the trick - I was able to place starter7 ( ticked as a stationary file) into the folder and it now appears in the favourites menu
I presume Library is hidden by default these days so hopefully this will assist others having similar issues
Many thanks once again