I think I have solved this with the project info and the layout options.
I keep my stuff simple to avoid brain-wreck! One project title one flow.
I wrote instrument, title and composer in the first part and then selected ‘use first page template first flow only’ with all layouts selected in layout options.
This seemed to bring up what I wanted in parts – instrument/title/composer.
If you don’t need to use the “1. Flow 1” flow heading in addition to the project title, make sure you hide flow headings using the Layout Option rather than manually deleting the flow heading text frame, which creates a page override.