I'm at the point of wondering about scrollable window box too, like with a mouse wheel, but for now we might have to use pagination technique, that is, press something to keep the content going instead of scrolling through things.
Here's a quick and dirty example: dl.dropbox.com/u/1990899/dialogue.capx
You can wrap something like that into a function for future reuse. Those are probably not the best choices of events to make it perfect but that's the idea.