Attached Login.zip contains a NetBeans 7.1 project (use RC2 or above).
At start it displays a first Login screen: use credentials demo / demo and hit OK button ==> you get to a second screen ... but its content is not refreshed.
For doing so we do (see App.java):

Scene scene = stage.getScene();
stage.getScene().setRoot(page); // this call is no longer working, the content of the scene is not refreshed.

The workaround is to create a new scene each time.