v5.2.0 is definitely the latest version. There's 2 ways to try and update:
* Install JFBConnect again. It should try to update all of the addons available for your site. Look at the after-installation page for Community Builder as well and make sure it shows "Installed".
* Unzip the JFBConnect package and install the plugin from the /administrator/packages/plugins/socialprofiles directory
I hope that helps, but if not, or you run into any other issues, just let me know.
Thanks,
Alex