To use it set up a TFTP server that serves the dongle to your MVP box. Then your able to use e.g. VLC to stream any video to it either via RTP or via UDP to port 1234 of your MVP.
Example:
vlc VIDEO --sout '#transcode{vcodec=mp1v,acodec=mpga,vb=4000,ab=128,width=720,height=576}:duplicate{dst=display,dst=rtp{mux=ts,dst=IPofYourMVPbox,port=1234}}'
If you have multiple MVPs you can use the multicast IP address 224.0.1.2 to stream your video to all MVPs simultaniously (don't forget to set the route, e.g. "route add -net 224.0.0.0 netmask 240.0.0.0 dev eth0") .