This thread seems quite old but I'll add what I have found to work in regards to sketchup crashing when attempting to slice a model.
I tried to use the zorro tool on sketchup 8 pro with little luck, but then again I only tried a few times so it could very well be working now. I couldn't figure out what the problem was, and really didn't put too much thought or effort into it. That being said, I have cut some very complex models in Sketchup 7 pro using the zorro slice tool without problems, but when I would try to slice the very same model in SU8 it just would crash as some people have said on here. Anyway, If it crashes in SU8, try SU7 and if that doesn't work chances are it is your model and maybe the way it is organized/layered. Hope that helps a little, SU7 always works for me without fail, larger models can take up to 5 or 10 minutes sometimes, but in the end it always works for me. Awesome tool by the way....

This as got to be one of the best plugs I've come across. Awesome job with this one....