I have done this before but canlt see to find it

, what you need to do is load the external xml document, put it into a dynamic text box and use actionscript to scroll it, i would have the box moving under a mask, and then a onMouseOver(Stop()) possibly and then link the text. I will have a looksie for you if i find it or just make a new one!
Thanks Shaun, FundamentalDesign