I just installed the Centova Cast on my server, I had some problem with authhash for my first radio station, somehow I played around and got the authhash generator on my admin login. But whatever I do I can't get the authhash generator for my second station. I keep getting the following error
"Server is currently up and public (no YP connection)
No authhash set which is needed for a public listing."

Is there anyway to fix that?

I don't have a huge amount of experience with the whole authhash thing (it really has nothing to do with Centova Cast -- it's internal to SHOUTcast DNAS 2), but basically that means you don't have a valid authhash set up and you need to configure it again.

Believe me, you're not the only one who's complained about the authhash thing being confusing to set up.  Be sure to follow the instructions at:
http://wiki.winamp.com/wiki/SHOUTcast_Authhash_Management