Hi Jerome,
Thank you very much for the details, it helps us a lot!
2) I logged in and checked the setup, and I don’t think you have set it up correctly. I assume you only want to show results where the “magasin” custom field value is “magasin”. For that, you should use a “hidden” custom field filter like so: https://i.imgur.com/TpQ7qHL.png
On the sources make sure to select the appropriate fields you want to search within.
