I remember the Mogensen generator from way back when (late 90s?). The algorithm was unusual but I mostly remember it for its ability to directly generate maps in different projections. As far as the program that you mention, though, I haven't used it. Doing so would require a Mac, which I just don't have access to.
These days I tend toward using Wilbur or Fractal Terrains (I have always cringed at that name) from ProFantasy. They are windows only, but the output is at least as good as the Mogensen generator.