Voice Response DirectRT using Vista

I've installed DirectRT on version 2010.1.107.0 on my lenovo tablet but the function rt:aud doesn't work for me. I also have DirectRT (same version, I think) installed on a dell workstation desktop running xp. This morning I tried the voice response stroop test samples and they worked! Recorded audio and response time perfectly.

Also, for some reason the update installer won't work on the Vista computer either. Has there been a recent update that would resolve this issue? Is there another way to get the aud and rec commands to work using vista?