I was having major issues dealing with the cable that Diablo Sport offers to connect the predator to your PC because I have Vista 64bit OS. If you have Windows Vista 64 bit edition, the cable Diablo Sport offers will not work.
Go here http://www.usbgear.com/USBG-232.html and get that cable. I just received the cable and it works great!
USB Gear's USB to Serial cable works with Vista 64
RE: USB Gear
Curious - the Vista 64-bit driver linked in the last post of the USB-to-Serial Driver thread did not work for you?
johnc <at> diablosport.com