CT Pro so slow

I am using CT Pro 3.0.1 for Mac, and I found many of its features are
so slow. I asked Chromix and was told that it was because the pro version
deals with much more details. I know it does, but it is still unbearably slow,
taking 50 sec. just to open and graph a 180KB tiny image in 3D.
Any change in features like channel constraint, coordinate mode, plotting
mode, etc takes several ten sec.
I want to know if others experience the same thing. I am running it on MBP
2.16 & 10.4.7. I found it is a little faster on my G4 1.25 Dual, but still slow
in any standards. I don’t think anyone wants to spend 10 min. just to make
a couple of changes to see the effects.
Is it not that slow on Windows?