OK, for starters, take a look at this post for instructions on how to extract the file and place it back in the receiver.arf (if you haven't gotten that far yet). When you say you edited it with Notepad, I assume it came up all garbled, right? Try editing it with Wordpad which can handle Unix style text files correctly. Otherwise I'm also attaching a Windows style streams.cfg file to this post that you can download which you can modify with Notepad and insert into the receiver.arf file. Rioplay can deal with both Windows and Unix style text files so that shouldn't be a problem.

The format is pretty lame really: A line that contains <title> followed by the title of the stream and then 1 or more lines containing URLs for that stream. You should probably make sure there's no extra blank lines at the beginning or end of the file as the parser isn't very robust.