Hi,
I think it would be a good idea to explain how to change/access the CRYSTAL or CEL environment variables since that is needed if a CS game is released. The variables should be changeable internally so the real system variables remain untouched.
The aim is that if a CS game is shipped, a user who has a CRYSTAL var set different to the CS game specific directory, the game probably will not run/work properly (I noticed that several times now). That should not be too tricky, but I don't have a clue.

Hi,
I have created a small game using the predecessor of that engine a while ago (that hasn't changed much since from GS 3D to GS A6) and I very soon got to the limits of the Game Studio (e.g. massive multistorey effect-loaded areas were not possible!). The Game Studio is definitely easier to use than Crystal Space, but with CS, you have nearly unlimited possibilities. It sure is a bit hard to get into the matter, but I think it's worth it. CS is very active atm (documentation rewrite, CrystalBlend,...) and has a great future I think. The choice is up to you (and it also depends on what you are willing to do). There is no networking standard provided by CS atm, but there is one other advantage: In Game Studio A6, you have to pay to get the save/load games support if I remember correcly. CS is totally free.
For engine features comparison, there is a page in the faqs: http://www.crystalspace3d.org/tikiwiki/tiki-view_faq.php?faqId=5
Hope I could help, GoodLuck

Ok, then there is something wrong. Have you installed the required libraries for CrystalSpace? Did you get any error messages during compilation or when running walktest? Which version of CS do you use? What commandline options did you use?

Yes, that sounds like the collision detection is turned off (or even broken?) in your "tech demo" (whatever app that is). This means you can 'walk' through walls/objects and since the outer plane of the room kind of has no material, it may look like an error, but that's just normal.