Good morning, David
I originally thought that it was a bug with the beta version as well, but soon it became apparent that it wasn't limited to that, but was based on something else (which I still haven't identified as yet).
Here's a bit more chronology on the issue:
I started trying to use it after I had already upgraded my internal test installation from 2.0 RTM to 2.0 Beta 2. When it failed, I thought that it might simply be because of changes to the beta code, so I pushed it to my public site which was using 2.0 w/SP1. It also broke. I then took it to my site at work, which was running 2.0 RTM, and tried it there, with the same failures as the other two sites.
During this time, I wasn't sure if there was a problem with my Affiliate Key or not, so I waited until I could get the correct info on the key. Also, once I found that it didn't work, I didn't remove the code outright -- I merely commented it out. In all cases, I was cutting and pasting the exact same code between all of my sites.
So, we had two sites on v2.0, and one which moved from Beta 2 to RC1 of v2.1 -- but the add-on still wouldn't run. Now, my test installation and my personal site had basically the same add-ons, but the work installation was more vanilla, and still there were problems. Each time I tested them, I was simply removing the comments from around the code, and in one case I restarted IIS, etc. I never did reboot the box, though.
Finally, I upgraded my test site and my personal site to the RTM of v2.1 on the 9th. Yesterday, while updating other aspects of my sites, I decided to try enabling the add-on again, and it worked immediately on the internal test site. After posting that here, I pushed the same code to the public site and it started working there as well. I guess I could try the work site today and see how complete the success is.
I have archives from all 3 sites pertaining to the code which existed since I started this endeavor, so in the upcoming week, I will perform some comparisons of the code and see if there is anything that stands out as being responsbile for the previous failures. Even better, if I can replicate on demand the conditions that caused the error, I will be pleased, as I hate loose ends in troubleshooting.
I'm very happy that it's working, however, and I hope that everyone else's experience is just a little less *involved* than mine.
Thanks again for all your assistance.