Update
Just to let everyone know, I spoke with Bill at X10 support and he has been great. While they are not aware of any manufacturer issues with the latest version of WS12a switches, they are going to replace the faulty switches I have running in my home. In total, I have 22 faulty switches out of 39 ordered and so this is great. I have been very happy with the level of support offered by X10. I have read some less than stellar reports, however, my experience has been very good. Which, as we all know, is often not the case today with most companies, let alone mail order/internet based ones.
I want to thank everyone for their time and attention to help be work through the potential issues with these switches. Your advise and wisdom was extremely valuable to me in diagnosing these problems and invaluable to me as I worked through the process with X10.
Many thanks, and I'll keep everyone informed of the progress with the new swtiches.
Thanks!