AFTER OVERLAY HAS STARTED:
Initialization based on when the host Overlay is the target of a start action. It can be from either another Overlay, or from Aura launch if the overlay is NOT initially hidden – as it will start immediately when the Aura launches. This event will not initialize when host Overlay is already active, even if it has been paused – only from its initial start. The host Overlay can be stopped & then when another Overlay starts it again, this action will reoccur.