I'm using Encore CS4, and I can't get the timelines to show up in the monitor, which makes it rather impossible to insert the chapter points. Audio plays fine, menus display fine.

How do I fix this?

EDIT: I used a video editing program to work out where to insert the chapters, and burnt an ISO. However, when I play it, the main menu acts as though it's just an image--none of the buttons actually do anything.