We are setting up a wordpress installation (one click app) to root.
In our development environment we generally build a site using an IP address rather than a domain name and then move to the site by changing the DNS settings to point the domain to the development IP address.
However, we cannot get to the wordpress administration using an IP address.
Is there a way to access wordpress in the root via ip address rather than the domain name?
If not, is there a way to change the domain name for the website?

You cannot install WordPress only on a website IP using HCnix. To get your website resolved, you can make entry of the "domain name" and corresponding "public ipaddress" in your local system host file after which you would be able to see how your wordpress site looks like.
 
I hope this will help you in seeing your website before its actual DNS propagation.

Thanks. That's what happens after new years. Your mind looses brain cells and you forget simple stuff.