If your other computer is displayed under the Syncables "Shared Computers" menu, but you are unable to see its media and document files, please check the following:
Make sure that you are signed in using the same Syncables Account on all the computers.
Check the "computers" tab in the Syncables preferences menu. Make sure the “Share my library on my local network” checkbox is enabled.
As a last resort, you may have to restart your computers and re-launch the Syncables application.