I have a Nas, and I have upload some video that I can see through UPnP A/V. Can I ask you if you know how I can insert this type of video?
(Sorry for my English, but I'm Italian).

I know next to nothing about Nas, but I searched a little and I think it's theoretically possible, provided you let the Nas feed a server on your network. Anyway, you must somehow make the files accessible from the web. You can serve files from your own computer on the web - provided you install a server software on your machine and open it up to the web. Without that - no. I guess this is basically the same thing.