After a year and a half, I'm about to give up and look for other options.
Even though there was not a lot worth watching through Boxee itself, and I had to depend on getting lucky to find a title on Navi-X that wasn't continually stopping to buffer, Boxee was worth the price because it gave me a reliable method of watching my local media.
That's no longer the case. After the last update, UPnP doesn't find most of my files (in any given directory it will see a few files but not the rest.) I saw posts stating that SMB was preferable anyway, so I finally managed to set that up. It wasn't easy. It works in that it can access the files...but it's continually stopping to buffer. Even though they're locally stored on a wired network, and I never had the Boxee buffer local files before, it is now useless due to constant buffering.
Unless there's an update soon to fix this issue (that, again, did not happen before the last update), I'm going to toss it into a box in the garage and buy a media PC.