Hi Paul,
Glad to hear that!
Try to read here:
What about Plex Server addon in the software center? - #68 by painkiller895
or better, the complete post.
Isn’t quite add on but …
Also try to search on this forum for “media servers”, …
Anyway, anything that works on CentOS 7, should works on NS 7.
Keep in mind that NS 7 is still in development mode!
Gabriel