Windows Genuine Advantage is a piece of software Microsoft use to make sure you're not ripping them off.
It is regularly updated. What you most likely saw was confirmation of it being updated, is all.
Microsoft couldn't give a monkeys whether your copy of Dreamweaver is iffy or not and they certainly wouldn't go out of their way to detect pirated software from any company other than their own and maybe any company closely affiliated with them.
So worry ye not
'Windows Genuine Advantage' If ever there was a misnomer...