http://bugs.winehq.org/show_bug.cgi?id=36001
--- Comment #5 from Susan Cragin susancragin@earthlink.net --- Windows Vista is the earliest version that can be used in a 64-bit system. See: http://supportcontent.nuance.com/dragon/12/doc/DNS_V12_5_ReleaseNotes.pdf page 11. I will use that in future. In 32-bit mode it still runs in XP.
As re. selecting 64-bit over 32-bit, NatSpeak is resource intensive. And I am expecting the next version (Dragon NaturallySpeaking 13.0) to have an entirely 64-bit version.