Recently I had to do a manual install via FTP because the theme I was using required it in order to have sample data installed (saving me a week of figuring out how the theme was setup). But, since I didn't use Webuzo admin to create it it isn't shown in the admin and I can't back it up either, at least not from Webuzo. Is it possible to edit a file and add it back in so that the admin sees it?
You can import the joomla installation in Webuzo and then take the back up of the same.
Just go to the Enduser Panel select the appropriate script and click on Import tab, give the directory name (if any) and then click on import.
This will import your installation and then you can manage it from Webuzo Panel.