I went through the same experience as you. One day I downloaded the drivers after reinstalling Windows and found it asking for a username and password. The old drivers are still on the site though, just hidden. To find them, follow these steps:

1. Go to http://www.razersupport.com.

2. Scroll down the page, and then click on the Drivers, Firmware And Manuals Download button.

3. From the Main Categories menu on the right side of the screen, click Razer Mice Products.

4. From the Download Categories list, click your mouse series.

5. From the Download Categories list, click your mouse model.

6. From the Download Categories list, click Drivers.

7. If the Legacy drivers are available, they will appear in this Downloads list.

The Naga ones are here: http://www.razersupport.com/index.php?_m=downloads&_a=vi...