You should be able to use the TCP vis without being root. This is most likely a security / firewall(on your localhost) setting that is hosing your networking.
You can use "telnet" and "netcat" (nc) programs to help debug what is going on. Make sure you are using ports over 1024, as traditionally, only root can bind (listen) on ports below that. Are you running solaris or linux? This sounds like something SE linux might keep from happening. Do you get any useful error messages from using the TCP VIs?.
