You can work on any page of your own in a separate .fla file and after setting the paths to your complied .swf file in one config.xml file, you can load it into the site! Plus, in the same config file you can also set the transition animation for transitioning your pages both in and out of the site as well as set the the vertical alignment, horizontal alignment, and z-index of your loaded pages. You can also control whether or not to stop the sound playing on the site (if you are loading a page that also has audio, such as the video player).