Cannot find "Maintenance tab", to insert the "license key"

The Avast program instructions say that to complete registration of Free Avast, it is necessary to insert the license key, by first clicking on the Maintenance tab, in the program.

I have spent hours trying to find a “Maintenance Tab”, without luck.

Can anyone please tell me how to find it?

http://www.avast.com/faq.php?article=AVKB9#articleContent

Did you manage to locate the Tab and successfully insert your License Key ?

As, as many of us have had problems with this aspect,have you also been able to successfully fully update the Virus definitions and engine yet and also dared to run a computer scan yet?