Problem:
There's no way to register or activate the add-in I bought.

Solution:
You must turn the add-in on. Go to Outlook, and click on the Sperry Software Add-Ins button. Now check the box just to the left of the add-in in the left hand pane.

A window with three options appears, "I'm ready to buy it...", "I bought it...", and "Continue Trial...".  Click on "I bought it" (even though you may have bought it in the past).

When the window asking for the order number appears, type it in, then click "Connect..." - this will bring you to the Sperry Software web site where your activation code will appear.  Copy and paste the entire activation key (including any punctuation like equals signs) back into the add-in window.  Then click "Activate..." and your add-ins will be ready to use.

Comments:
If the add-in does not request that you activate, and you have done it on that machine at some point in the past, it will not ask you again as it remembers.  You will have to activate if you have a new machine, or if your machine was rebuilt. 
If you click on the Sperry Software Add-Ins button and the Configuration window does not pop up, follow these instructions.