OK... now it works. The graphics are quite smooth, even if the detail is not too great and it comes nowhere near the graphics of my PC (1024x768 on a TNT2/16 MB VRAM/500 Mhz PIII/128 MB RAM). But hey, it's a two years old PORTABLE machine.
Now I have to decide if I want to run CM at home with good graphics, or if I prioritize mobility, playing while travelling.
The relevant step was the disabling of the ATI software. It is OK to keep the "ATI Driver Update" file in the system, but no other ATI components.
I have the entire Quicktime 4.01 set enabled (includes Quickdraw 3D and Quickdraw RAVE).
Some more facts of interest: I have no chance to tell CM which resolution to use. I normally run 1024x768, in millions of colors, but CM changes to 640x480 wihtout asking. Probably it looks at the amount of VRAM or something.
The Preferences file was not created until I managed to get the graphics running. Previous attempts yielded no preferences file anywhere in the system.