Thank you for the welcome, and for the advice! I will try reinstalling it to a new directory, although I have user access control turned off and my account is an administrator on the computer. It's worth a shot, at least.
I also made sure the .ocx file was in system32 and even ran a command-line register command to make sure it was really registered.
Sorry for the late response - I had been out of town and just got to get back to this. The one very bright spot for me is that my Reader came in while I was away and I love it! I'm eager to try out some of the interface hacks and, of course, to start reading with it.