I’m sorry but there are no public WinpkFilter builds with Vista x86 support available for download. The normal x86 package you could get from this site supports only Windows 9x/ME/NT/2000/XP/2003.
Windows Vista (both x86 and x64) are supported by NDIS IM build of WinpkFilter. In the meantime WinpkFilter NDIS IM used only for Windows XP/2003 x64, but it can be also compiled for x86 and used on Windows Vista x86. As soon as Vista is released for public we will add new WinpkFilter installation packages for public download (in the meantime it is available only to registered customers on special request for testing purposes).