So, you are writing an Air app (or more likely just imported one from somewhere), you try to debug it and the AIR Debug Launcher (ADL) just sits in the Dock (on Mac) and doesn’t open any window, doesn’t throw an error, nothing. Well, you will want to check that you are not using a Flex application class but rather the Air application class; i.e. <s:WindowedApplication>. Duh :-)