I think I have fixed my problem. At least initial testing is going well. For those following the thread, or may have the problem in the future, this is what I found out. I thought I was using the latest versions of the software but was not. The documentation for both WeatherLink (5.9.2 dated 3/26/10) and VWS (14.01 p31) was a little lacking in the matter.
I was using USB not utilizing a virtual comm port. This worked fine for weather but VWS would crash shortly after opening HRD. Although it acted like a comm port conflict, I wasn't using a virtual serial port so could not find a conflict. After everyone had had such bad experience with the USB version I was afraid to change anything but I did. I decided to try a virtual comm port and see if I could force ports eliminating the problem.
Davis updated the drivers but left them out of the latest software version and didn't identify the drivers. Digging around for the umpteenth time, I found driver updates that seem to work. Following the instructions to utilize a virtual serial port (VSP) the file included in Weatherlink did not work. Instead download the Vantage DLL package dated 1/29/10 and install. Although dated three months prior to the software release, this seemed to work. I then reconfigured for serial comm ports in both Weatherlink then VWS and it seemed to work, at least for now.
Why a hardware serial port was conflicting with a USB port is beyond me but I'm not arguing with success.