This thread has what you are looking for.
http://forum.arcadecontrols.com/index.php?topic=128951.0Essentially copy the code below into a text file and once saved rename the extension of the file from txt to ahk
m:: run smccmd --speed -3200,,Hide
n:: run smccmd --speed 3200,,Hide
return
You may want to vary the speed depending on your motor and the keys to rotate which are 'm' and 'n' for the code above.
You need to install AHK. Once you have AHK installed you double click the ahk file to have it running in the bacground or put it in your startup folder so it runs on startup. AHK scripts normally just sit hidden in the background. Mine show up in the system tray (windows xp).
I just tried the code above and worked fine.