Here's what I did:
(1) Browse to your folder(s), and add at least one as the "Favorite"
(2) From App->Contributed App->Jukebox. It'll say you don't have any jukebox installed, then select install one
(3) After the jukebox is installed, run it to scrap the info for your movies
I followed two YouTube clips (I'm not allowed to post links here; you can simply search "Xtreamer Jukebox Guide" in YouTube).
It seems like only Movies is supported currently (ie, no TV Series, Music, Photos, etc).
BTW, I'm using a USB drive and I can't access the Web Interface (got "Jukebox is not installed" error). Not sure it's because I'm not using an internal HD, or it's a limitation of XtrAIOS? Anyone can access Web Interface (like http:\\myxtreamer\jukebox)?