When creating a new document, you must give access permission to the role into the functionalities tree "directory" where you are storing your document; you have to give permission to the menu item you are using to access your doc as well. That same thing applies for your parameters (check for given permissions).
Hope that helps.
However, i suggest you to check your logs to see if you can find more info.
Logs that generates when running your server and the engine you are using. In your server logs directory you can check for catalina.out for example in case you're using tomcat. Check out SpagoBI.log, and SpagoBIJasperReportEngine.log (or something like that) too.
If you're in Linux try monitoring those files with "tail -f yourlogfile", in win if i remember well once i used that command trough cyg-win but not sure