PlexConnect and Apple TV 3

Hi, I am totally non-technical (and ancient) but have just bought a Synology DS216se to store all my video and music files. I play my mp3 music through a Cambridge Audio player and now would like to watch my Apple formatted mp4 movies on my Panasonic TV. Is there an idiots guide to using PlexConnect with an Apple TV 3 please? I can play the movies through the Apple TV using a wireless Seagate HDD, so no recoding is necessary, but I would prefer to use the NAS now if possible. Anyone willing to take the challenge and help this Old Fart out?

Basically you need to install in the DS216se:

  1. Plex Media Server and, after completing all its parametrization so that your media libraries are indexed by Plex
  2. Decide which AppleTV application (trailers or WSJ) you are going to use to access Plex (instead of its native funtion) and install PlexConnect using these instructions