The demo site is using seperate installs for each page and is displaying them in a wrapper. Are you just looking to achieve the same functionality or use the exact same method?
What i mean is, when you are on any page on the internet and want to link to a certain template within the demo. RocketTheme uses that sort of links. I can't seem to get that working in my setup.
The query_string there is obviously something custom that was done by the RT Team. Have you written a similar 'redirect' script - or are you just trying to throw random variables at nothing in particular?