Hi from Costa Rica
The AstroStepper cant work for some windows timing limitations
I have talk with Mel bartels about it many times and a really good posibility is to make a Linux version of the Scope software that I will to try some day on the future.
Maybe the last windows chance will be using Vista with some multicore procesor (dual o better a quad one) where u can find really windows multitasking
I have made a little program for windows in order to see what to expect, u can control your stepper based system (mels one) using a game pad or joystick... maybe u want to try it
here is the link:
http://mantsoft.googlepages.com/software