I assume mecharujirou used the normal way to check the WA version, clicking on "Nullsoft Winamp..." in the main player's context menu.
The main site has been having random problems recently. Not downloading anything or downloading the wrong version of stuff.
Winamp Pro 5.666.3516 fully-patched - cPro2 XUI Unity ECNMY skin
Windows 7 Home Premium 64-bit SP1 desktop - Logitech Z906 5.1 speaker system