Jerome,
We use Transifex to manage our translations. French is one language we support and you can see it's progress on this page:
www.transifex.com/sourcecoast/jfbconnect/
Currently, it shows translation status as 25%. Almost all of those are the front-end strings. Much of the admin area hasn't been translated.
We include all language packs in the JFBConnect releases. You should see the fr-FR.com_jfbconnect.ini file on your site already in the langauges folder. If not, let us know. If you make any updates to the French translations, please feel free to send them back to us and we'll make sure to include them in a future release.
Thanks,
Alex