Hi
I've not tested to see if this is causing your problem, but it looks like you're missing a ' after the originalTrackNumber term; it should be as below:
sortcriteria='+pv:numberOfThisDisc,+upnp:originalTrackNumber'
It's very possible that by missing that part out, the containers below it will not function as expected (or at all).
Hope that helps
Bri
PS See
here for a similar my answer to a similar question about sort order (and why it's the way it is), and also
here for links to more information about four custom tree packs I've created. I've added both the disk sort and track sort orders to the folder views in all of my custom tree packs, so these might be of interest either as a complete replacement tree option, or just for lifting sections from it (i.e. containers) to use when building your own trees. There's also a link to instructions (with screen shots) on how to add the custom tree packs to the QPKG version of Twonky (and thus it also shows where the existing ones reside on a Qnap).