Custom registration & login

I’m using the latest version of Register Plus to add some custom fields to my registration form(http://kasten-online.be/wp-login.php?action=register)

I want to get the registration and login forms to display as regular pages on my site (http://kasten-online.be/).

The settings for Register Plus allow me to customize the CSS’s of the pages but I have no idea on how to make it look like just another page in my site.