There is a considerable amount more to do that just uploading the files.
Check out the read_me.htm file in the root. That lays out what you need to do. In a nutshell, you will need to configure your host to parse php, create a MySql database, use the included sql file to built the database tables etc.
The documentation that webassist provides is pretty detailed.
I also suggest that you remove the link to your site, or remove the pages until you get your server configured to parse php pages.
Hope that helps some.
Tom