I've been working on distributed Network Rendering using Vegas 9.0a with three computers. The stitch host is running Windows 7: both it and my Vista renderer //work// whilst my XP renderer fails with the message: "The requested address is not valid in its context 255.255.255.255:53704" despite the fact that there is no obvious difference between the settings on the two renderer boxes (my subnet is 255.255.255.0, by the way).
I found one comment mentioning this error as being solvable by deleting all renderers and re-entering them but this has not worked for me.