Timeline troubles - any advice?

I’m a Flash newbie and am just learning the ropes. I have a project where I’m to build an interactive timeline. I’ve started on one version and it’s not functioning as well as I would like. I recently found a Flash timeline that I would like to try and model my project after. If anyone can help me deconstruct how to build a similar timeline I would appreciate it.

The example timeline can be found here: http://www.doncesar.com/timeline/Flash/