I've been using the SAPI 4.0a since 2000. I wrote an air traffic control program in visual basic 6.0 (atcsimulator.com) that makes exclusively use of that API for both TTS and Speech recognition. I also have the SAPI 5.1 installed on my PC, and most recently used Visual Studio 2010 with the built-in SAPI for the .NET platform running under Windows 7. So, I would think one of those would work with the Enhancement pack. SAPI 4.0a is still working under Windows 7 when I run ATCsimulator2.
But I am not running Windows 8; and probably won't be anytime soon.