It looks like you have the PowerCMS up ok, are you able to insert any new content? The interface you are getting to just seems to be an empty one with no content. So long as you can add the content you should be fine. Let us know if you cannot.
As far as db manipulation goes that is not something that PowerCMS does. It really is just for content management and will not help you to manage users or logins. It will allow you to create content for your site that you add to the site with the code snippets that are provided in the admin area.
