It's been pointed out that there is an uneccessary transition to the reset skeleton state from the coffin lid open state in the statechart below (thanks Richard). I've re-drawn it and added another state to play a 'creaking door' sample as the coffin lid opens.
The state which opens the lid without playing a sample is used when the lid opens from the doorbell button. At this time the thunder sample is playing and the creak sample would be inaudible.
Here is the new statechart: