Stéphane,
For the avatar faces, they likely aren't showing because the height isn't tall enough. If you have the header, stream, and faces, the min-height you'd need is something like 500 or 600 px. Try increasing it, or removing the stream/header, and the faces should start showing.
As for auto-posting content back to your Facebook Page, that's not something we do right now. It's something we're hoping to add later this year, but it gets very complicated to do it right (no double-postings, don't post until the article is really ready, only from certain category options, etc). Until then, the best option is to simply create a wall post about a new article on your Page itself. Tedious, but also allows a little more custom information to be entered before you link to it.
Hope that helps! Definitely glad to hear you're liking JFBConnect so far. If you have any recommendations or feedback, we'd love to hear it!
Thanks,
Alex