our servers are 64 bit, users PCS 32 bit xp with qv plug-in installed locally. All access is via the plug-in directly from PC (laptops or workstations) to server using the qvp protocol. All the machines are in the AD which uses trusted domains. We don't access via terminal servers - we used that as a workaound during the migration to the AD for users whose machines were still outside the domain as we use NT authentification. But is was only temporary.
We're on v8.5