Using Pro Sites & Blog Templates

Hello, I have been told that I can start a service using the Pro Sites and Blog Templates where I can sell a customised Wordpress website with themes available, custom post types and data etc.

I have attempted to do this following the usage guides however I do have some questions...

1. When I visit the following page on my main website I notice that it just says 'You must first login before you can choose a site to upgrade:' however I want the user to sign up and create their site from this page. I have setup a trial for a day in the settings of Pro Sites so I want users to be able to sign up and setup their site from here. How is that possible?

2. How do I choose the theme, custom post types and demo data to display on every Pro site that is created after the user has signed up? I have been told that I should use the Blog Templates plugin but how do I make it so that when a user signs up they have a Wordpress installation with a theme selected and demo data on the installing?

Thanks, Nick