@keropi:
I am running OS3.9 here with the latest CGX4 and a CyberVisionPPC and I constantly have ~2030kB chipmem when only using rtg screens and no audio.
As already mentioned you should set the Workbench preference for Images to be stored in "Other memory", but other than that you should make sure you have the OS3.9 supplied picture.datatype. If you have BB2, it should be version 45.17 dated 2002-03-19 if you do a "version SYS:Classes/Datatypes/picture.datatype FULL".
Other than that, here are my CyberGraphX settings:
EnvironmentToolTypes/Patrik