The /media directory is writable. Have you checked the /media/sourcecoast and it's sub-directories? There's no reason they shouldn't be writable, but something obviously isn't right.
Again, have you tried to re-install JFBConnect again? Those files should be installed during installation by Joomla. You can check the XML files in the com_jfbconnect.zip files jfbconnect.xml file and the /packages/modules/mod_sclogin.zip file's XML file. Both of those packages install some files in the /media directory. The XML files are parsed *by Joomla*, so if they aren't installed, it means that Joomla's having an issue doing so.
If that still doesn't work, you can copy the /media directory from the install package to your /media/sourcecoast folder and that should clear things up. If not though, again, just let us know.
Thanks,
Alex