So Much Info Available.
I recently purchased a Vag-Com and was thinking along the same lines regarding printed material that details the all menus and sub-menus accessible via the hardware/software. After looking at the Ross-Tech website and thinking about the versatility and cross-year compatibility built into the system, I can see the huge under-taking it would be to provide detail specific to all of the controllers accessible. If they did provide a detailed all inclusive manual it would probably be huge volume(s)along the lines of a "Bentley" type manual. When your consider the program reads the controllers specific to the model being scanned and not all models have the same controllers/features it would be a lot of work and paper to detail so many applicatons.
I know it seem strange that you have to be tethered to the vehicle even if you just want to "browse" the functionality in the program but I think its your only option. This site and the RossTech site one are cool in that when you run into something you don't understand a click is only a search or e-mail away.
I was also thinking it might be a cool project for someone to research and document "all" of the functionality available through Vag-Com. This would probably years of work though.