The enhanced blitter is avaliable only in FBA 32 bit releases (Windows Binary and Windows XP Binary), probably you're using the "Windows 64-bit Binary"... in any case, the 32 bit versions can be used in 64 bit OS without problems or limitations!
You want the Windows Binary - the descriptions on each are pretty clear.The 64-bit version even tells you the D3D blitter isn't included.
hmm that's unfortunate they would link that exe, maybe we shuoldn't link a 64bit exe at all until the issues are resolved..