CDRwin 5x doesn't work, so better off using something better.
That's the only solution I have for you lol.
Just so you know, it isn't part of the old CDRwin it's from some other company that tried using part of the pradus disc juggler engine (at a really failed attempt).
So why not try going back to CDRwin 3.x or try DiscJuggler or something else instead.
Ofcourse if you are really set on this version, just wait till someone posts a working keygen/serial