Alejandro,
Sorry for the delayed response.
There's no way to have JFBConnect tie into the JomSocial activity stream right now. It's an interesting idea, and may be something we look into in the future to post open graph actions easier.
Right now, you'd need to have an Open Graph Action plugin for SimGallery that would post the action you're looking for on an upload of an image. We'll be working soon on new Open Graph plugins for multiple extensions, and will be putting together a good guide on how to create your own, if you know PHP or are a developer. The plugins themselves are usually less than 100 lines (about 50 lines of 'real' code). We've tried to make them very straightforward and easy to create.
Hopefully, we'll be able to create a SimGallery plugin over the next few months. You may also be interested in contacting the SimGallery developers to see if they'd be interested in creating one. We'd gladly help them out however we can, but haven't used SimGallery before, so it would take a bit of research for us to do it.
Hope that explains, but if you have any questions or feedback, we'd love to hear it.
Thanks,
Alex
Custom object + custom action
