Changing the name of the machine is a little tricky although you can change the IP adress without any problems, you just change the IP and restart (given that you used host name during installation)
If you change the name of the server, you need to change it everywhere in Nice System Administrator given that you're using the naming host not IP in the configuration. More important you need to change the SQL Instance Server name, you can find the procedures on google.
Changeing the name of the machine might also involve in changing the host names in the ServerBin folder in the .config files.
Keep in mind that such cloning is illegal from Nice's point of view.....