I don't know whether you are working on PVR Stalker client (as I recommend) or IPTV Stalker video add-on?
The directions for PVR Stalker explain everything that has to be done, including mention of the serial number and Device ID. I gave the directions on the first page of this thread, and I'm repeating them here:
http://iptvtalk.net/showthread.php?1...et-up-tutorial
The 404 error sounds like you have mistyped the portal address on the configuration page.