You will need latest version of confession script to make this theme work, check it out here:
About One page
One Page is an premium theme for confession script which cost many hours of work. I bet you will love it. Well done better than well said, let’s check the demo instead of reading dummy text:
Home demo: One Page
Admin demo: Dashboard
Admin account: admin/admin
Let’s check the customizator at Settings -> Theme customization 
What make Onepage special?
How to install and customize?
There is a documentation inside the package, install will only cost one minute (3 steps).