When you are in Configure Storage Service section in Test Studio installer, there is a button "How do I change the Storage Service account".  When you click this button, it will try to open the following page:

http://www.telerik.com/automated-testing-tools/change_storage_service_account.aspx

The correct link is:

http://docs.telerik.com/teststudio/user-guide/installation/change_storage_service_account.aspx