There is one thing you need to keep in mind when you add gamepad support to your Greenfoot scenarios. If you have it, then your game will not be able to be played on the Greenfoot site. This is due to the fact that there is no Java support to connect to a gamepad via a web application. However, you will still be able to export your scenario as a desktop application if you follow the simple steps at http://www.greenfoot.org/doc/gamepad_export.