Thanks Tom,
What I did: I downloaded latest available ZDS II software and installed it. I'm not going to use it at this point (see earlier comments) but I did get the 64-bit USB drivers. I updated the USB driver via control panel and was able to successfully connect to the SmartCable using SmartFlash Programmer.
If I may recommend that the SmartFlash Programmer download (SFP2.2) be revised to include both the 32 and 64 bit versions of USB drivers. Currently only the 32-bit versions are part of the install.