Thanks for this explanation. I start to see how to solve the problem.
Option 1: I can defined a fix number of editable fields on the back end, and add a browser like one of your examples to select multiple files. I believe this would result in a list of files which is then pass to back end. In this scenario I wonder how to map the selected file to each editable defined...
Option 2: Not limit on uploaded file, though require some configuration in the web server.
I have no idea on how to implement this, but that's probably what you wanted to show in the tutorial you mentioned earlier.
I feel that code wise, option 2 would be more elegant, but option 1 is perfectly fine to address my problem.
If you don't mind giving some code details on how the mapping between the several editable input and the client file browser, I'll be very happy