You can try contacting Thomas at "thomas dot bruckner atsign netway dot at", maybe his address is still live there. But he hasn't been active for a couple of years.
As to the Model Creator - I've toyed around with it some time, and it is rather tricky; not to say lacking user friendliness. But since the tool's release seemed to be an afterthought (In 1999 he wrote "- I have thought rather long about whether I should release my ModelCreator as it is now (it is in a pretty chaotic state and I don't have the time nor the energy to change that)."), I think there is not much hope that he developed the tool much further. Maybe a commercial 3D Model Software will give you more joy.