There are some bugs in the underlying libraries that we use, which can occasionally cause a freeze, particularly at high generation number. So far as I know, those have not been fixed. We’ve been thinking about rewriting the software with a different voronoi generation library, but have not had time to do so yet.
You may find it helpful to download Processing and run directly from source, so that at least you’ll get an error message when the core crashes.
And, you may find it helpful to save output at lower generation numbers. We’ve generally found things to begin to converge at around generation 40, and look best after generation 100.
