Actually, if the black frame issue happens in Starling 1.x, this is a completely different problem than what I tried to fix in 2.x. In the later Starling version, the reason for a black screen was that Starling didn't redraw it (thinking that it's not necessary, and not having realized the app had been interrupted).
In Starling 1.x, the scene is always redrawn in every frame, as long as you have called "start()". Typically, you stop Starling when "Event.DEACTIVATE" occurs, and restart it in the "Event.ACTIVATE" event (probably that's part of your startup class). Could it be that in the scenarios you describe, that "ACTIVATE" event is not being dispatched?