The Apple TV version is different from the Mac version, as for example on an Apple TV local media can not be be stored. Therefore, the Apple TV version provides (so far) only access to media server and their media.
Please download also nessViewer to proof whether the full features (e.g. editing of media, internet browser, media shows, media server) will fit your needs in a better way.
We will update nessMediaCenter regularly in the same way as we did for nessViewer the past 3 years - informations about each update can be found here.