From the information the report provides, there isn't anything obvious that should prevent speech recognition from working, as far as I can see
Something I do see, that's not usually an issue, but is worth trying just in case:
Hold the Ctrl key on your keyboard, and click the wrench icon on VoiceAttack's main window, then in the list of recording devices double-click the "PRO X 2 LIGHTSPEED" device, click the "Advanced" tab, then disable (remove the checkmark for) the "Allow applications to take exclusive control of this device" option, and click "OK"
Restart VoiceAttack and see whether that makes a difference.
I've also attached a profile to this post for you to import; when the profile is active, if the speech recognition engine generates any recognition events, they should automatically be played back to you.
If you hear nothing, the speech recognition engine basically isn't detecting anything that it can even vaguely consider speech.
If you do hear something, how does it sound?
Lastly, I'll note that the installer for the Microsoft Speech Platform 11 runtime uses a wizard, I.E. it'll ask you to accept a license agreement and such, and the installers for the Microsoft Speech Platform 11 engines should show a window and show a UAC prompt asking you to allow the app to make changes to your device (assuming you haven't turned off UAC)
Especially the former shouldn't just disappear; that's an indication it's crashing.
If this is happening with one specific installer, it could be a corrupted download, but if it's happening with more, and re-downloading doesn't change that, something is unfortunately amiss with your system.