How to activate a gadget after registration:
Vista Sidebar gadget
Please press a small button (with a "wrench" depicted on it) that appears when you hover your mouse over the gadget. This will bring up the gadget settings window, where you need to select the "Registration" tab. Enter your username and registration key, that you received before.
Google Desktop gadget
Please press a small button (with a triangle depicted on it) that appears when you hover your mouse over the gadget. This will bring up the gadget's menu where you need to select "Enter Registration Info". Enter your username and registration key, that you received before.