When you say "created as a new site on another server" do you mean you installed Kentico and added a new site from the UI or did you simply copy the files and database to that new server? If you're attempting to create a new site, it will most likely fail since the site id's and code names could be different, not to mention the node and document info.
Are you getting any errors when using staging? Anything in the Kentico logs or IIS logs?