Designing a class - advice

I am planning to build a flash presentation. To make it easier to update, I intend to build the presentation so that it will grab all of it’s content ( text for slides, paths for images for the background & logo etc) from separate specified XML files. For example, we would have a SetUp.xml file that flash would reference for all background and logo images and a slides.xml file that contains all the slide information etc. I have prototyped this in AS3 on the timeline and it is working fine. I have an xml file loading in the slides and I am populating a text field with this data and then navigating backwards and forwards using some buttons. So far so good. I can see this approach is going to fall apart a bit though as the content and project complexity grows in size. I have been reading a lot about oop in AS3 and really want to construct this project with this in mind. My question is, how should I best go about structuring my classes for this? Should I set up an XmlProcessing class, that I pass a file path to, which will process any xml file I pump into it, creating an array ready for me to access? Should I create a Slides class and button Navigation class? My brain is aching a bit with this. I am wondering how best to approach this.

Any advice would be greatly appreciated.