The Movies, TV Shows and Music lists on YATSE use the Library of your XBMC installation, which is probably empty.
I'm assuming that you get a message saying "No media. Please use the refresh button to synchronize your library or refine your search." At least, that's what I get! However, if I do synchronize, that message goes away, because I've scanned all my media, I just haven't synchronized YATSE. In your case, that won't work, because the Library itself is empty.
However, if you go to the "Files / Playlists" option on YATSE, you should then have a selection of "Video Files", "Video Playlists", "Audio Files", and "Audio Playlists". In the case of the two files options, you should have a "Database" Folder, an "Addons" folder, and then one folder for each source you've got defined.
But it's not really very useful. You really want to get that stuff scanned into the Library, and I don't think it's possible to do that from YATSE, other than by using its ability to control the selected item in the XBMC user interface, and making XBMC do the scanning. But if you can't *see* the user interface, that's not really viable.
Oh! Wait! I've just had a thought! It's possible to configure the music library to update on startup. In your userdata directory, you should have a guisettings file, which is an XML file containing a section:
Code:
<musiclibrary>
<albumsscraper>metadata.album.universal</albumsscraper>
<artistsscraper>metadata.artists.universal</artistsscraper>
<backgroundupdate>false</backgroundupdate>
<cleanup></cleanup>
<downloadinfo>false</downloadinfo>
<enabled>true</enabled>
<export></export>
<import></import>
<showcompilationartists>true</showcompilationartists>
<updateonstartup>false</updateonstartup>
</musiclibrary>
Change the updateonstartup value from false to true, save the file and then reboot. It should, if everything goes right, then load up your library. Of course, the only way to tell whether it's doing so will be to keep resynchronsing your YATSE, and it's not a fast process, so you might have to wait a minute before you see anything at all (and if you've got a large library, it can take hours to complete).
ETA: In YATSE, hit the plus symbol in the top right corner of the screen, and then select "Scan Audio Library" (or Video, as you need).
I'd recommend checking the YATSE Files / Playlists option first, just to check whether you've got your sources configured correctly. And, seriously, it's going to be much, much easier if you can plug it into a display, just to get the whole setup operational. You can unplug it again later, if necessary.