Not sure if this is a bug or my hardware but when I show Habitable zones it lags really badly no idea why but below is my hardware specs.
Windows 7 Home Premium X64 bit
128 MB Video Memory [It has complained about this before but does not seem to affect performance.]
2 GB Ram
Graphics Card: NVIDIA Quadro NVS 135M
Processor: Intel Core 2 Duo CPU 2.00 GHz
Other then that it runs very very nicely.