The Squeak scripting facility is quite different from the one in VW. Is the squeak version stable ?
The original implementation I did for Squeak had a completely different scripting API as the model is not graph based. I haven't touched it for years, but it is also pretty stable and worked quite well for what I was using it for. You can get it here: http://source.lukas-renggli.ch/mondrian.
Doru and Jorge incrementally changed my implementation to provide an API that is close to the original one of VW. You can get this version here: http://www.squeaksource.com/Mondrian. I've recently used this "official" version, but can't comment in detail on the stability as I only used a small sub-part.
Lukas