Error handling

Hello,

The error handling in community surveys is strange.

If a user tried to take a survey which he doesn't have permission for or if he tries to retake the survey, an ugly red and white 401 error with no site template loads.

However, on the demo website of this component, if you try to re-take a survey, one gets a nice joomla formatted system message with the rest of the site template loaded, saying 'you have already taken this survey'. How do we get errors to appear like they do on your demo site?