OK, so I have it working !
I created a “reporting” table with just the consolidated data I wanted (which comes from several other tables).
I have two buttons on my page…
The “Export CSV” button is hidden on page load.
When the page is loaded, I delete all the CustomerExports created by this user.
On click of “Create Report” I run an API workflow on the list in the repeating group …
Which creates entries in the Export table.
When the number of entries in the Export Table created by this User is = to the number in the Repeating Group (i.e. the Export is done) … the button shows.
And then you download the csv from the export table with this button.
As long as you don’t log in with the same user twice, it should work across multiple users.
Will put an example up on BuildingOnBubble at some point.