Help activating game Zomboid Thread

i just bought Project Zomboid here on Desura. but i downloaded the game before downloading Desura client. Now, to activate my game do i need to download it again with the client or can i somehow link what i downloaded to the client ?

I got my key and the game files are already in place and the client is running.

Found a page on the client to activate my game... but it asks me for a projectzomboid.com username and pass.... i dont have any... that i know of.. and i went to the page and i cant find any signup or nothing like it. =S

Im so lost here..

Plz help

If you did not download the game from here Indiedb.com or here Indiedb.com then the version you're working with is old. The new versions do not require logins.