Okay, that's something the author of the server has to answer, but I could think that the server failed to bind to the domain/url and the port, i.e. on my Mac I can't bind a service to port 80 without administrator privileges.
... and while reading the full error message, it looks like that the dns (server name) could not get resolved. I assume, you're running this on your local machine and the this machine has no public URL / dns entry? Try localhost first.