The suggested usage of the isEnabled flag

distriqt.extensions.pushnotifications.isEnabled.as

var hasRequestedPermissionsOnce:Boolean = false;
// You should load hasRequestedPermissionsOnce from some persistent storage, defaulting to false 

...

PushNotifications.init( APP_KEY );
if (PushNotifications.isSupported)
{
	if (PushNotifications.service.isEnabled)
	{
		// Notifications have been enabled by the user 
		// You are free to register and expect a registration success
		register();
	}
	else if (!hasRequestedPermissionsOnce)
	{
		// You should implement hasRequestedPermissionsOnce somewhere to check if this is the first run of the app
		// If we haven't called register once yet the isEnabled flag may be false as we haven't requested permissions
		// You can just register here to request permissions or use a dialog to delay the request
		register();
	}
	else
	{
		// The user has disabled notifications
		// Advise your user of the lack of notifications as you see fit
	}
}

...

private function register():void
{
	// You should save hasRequestedPermissionsOnce to a shared object, file or other persistent storage
	hasRequestedPermissionsOnce = true;
	
	PushNotifications.service.addEventListener( PushNotificationEvent.REGISTER_SUCCESS, registerSuccessHandler );
	PushNotifications.service.addEventListener( PushNotificationEvent.REGISTER_FAILED,  registerFailedHandler );
	
	PushNotifications.service.register( GCM_SENDER_ID );
}

// com.distriqt.PushNotifications