The transfertext command asks for a specification name. This is what help says about it:
"Specification Name The specification name for the set of options that determines how a text file is imported, exported, or linked. For a fixed-width text file, you must either specify an argument or use a schema.ini file, which must be stored in the same folder as the imported, linked, or exported text file."
The code has some specifications named in it but they needed changing because the data was in a slightly different format. Nowhere could I find where these formats were saved.
It turns out that the only way to find them is to use the Text Import Wizard advanced options and there they are. You need to pretend to import a file and get about half-way through to define a new spec and save it.
And then I got "Property Error" messages which I worked out, after some head scratching and web-searching, meant that my database was over 2GB at which Access fails.