While working on the tutorial file, during drag and drop to the header to view the dropped document, something went wrong and the dragged text was inadvertently inserted in the wrong place.
Cmd-z could not revert.
I have a second install on my mac mini from where I can save / copy the tutorial.
Where do I need to put or restore the new version of the file to be able to call it from the new project dialog box? (and overwrite the faulty one)