The AudioMASTER forum is very quiet, so I posted here...
I have experimented, and they appear to be working together. AudioMASTER requires TestStand 4.2.1 (not TestStand 2010) to be installed prior to the AudioMASTER installation, so I installed both TestStand 2010 and TestStand 4.2.1. I then had to manually copy the AudioMASTER TestStand components (icons, typepalettes, steptypes\mx_types) in \\users\documents\public documents\national instruments\teststand 4.2.1\components to \\users\documents\public documents\national instruments\teststand 2010\components. TestStand 2010 prompted me to update the types and .ini files when I opened and then closed TestStand 2010.