RAF and back button

Can anyone tell me what msg event we should be looking for when the user presses the back button to exit an RAF ad?

RAF.showAds() returns a boolean: True means ad played to the end, False implies ad was exited with Back.

There is a way to disable exiting ads, although i advocate not to do so but do something else - either absorb the skip, play another ad or ask a ransom :twisted: