If you zoom in while caching, does it fly back out to ~1000m or stay at whatever level you zoomed into?
i like it, it's fast! the 1 second really means 1 second!
BTW, for the Windows people, there's a all-in-one perl install project going on that you might find useful. It gives you perl, a lot of the graphical bindings, plus gcc and all the other tools you need to build most C based libraries.