Okay... Seems like I solved the problem. When you install SP1 with Vista, the default HID drivers are no longer recognized by Vista itself. (??!)...
Anyway, here's how you solve this:
Go to System-->Control Panel-->Device Manager
Right click on the 0/16/16 which you should recognize as a USB device with a '!' on it.
Click on the "driver" tab and select the "update driver" button.
Pick the manual option to find the driver yourself and use the following path
Windows will warn you that this driver is unsigned but just ignore this and go for it.
Immediate success... thank you Bill Gates (sheesh)