Great job for making this happen! It's stable unlike the other tries I've tried before.
One problem, though: a lot of modern 64 bit games and things can use only 64 bit voices, so we really need to brainstorm some kind of way to bridge it. Perhaps make a generic forwarder SAPI voice (kinda like NVDA SAPI) that will then call a 32bit executable to call the 32bit ibmeci.dll or something. It sucks not being able to use it in 64 bit things.