Hey,
media-explorer has been broken for a while, and didn't see any
upstream development since 2013 as can be seen here:
https://github.com/media-explorer/media-explorer/commits/master
The versions of clutter, clutter-gst and GStreamer used are positively
ancient, and the grilo version is the old API (0.2).
Shame it's going away, it was a nice and simple "set top box" type UI,
which could have found more use.
If anyone wants to work on this upstream and downstream, drop me a private
message, and I'll do my best to help revive it.
Cheers