Something seems to be wrong with my Nuendo rig. I am making some tests with Nuendo 5 and I have an issue that I had not with v4.
When I am in Direct Monitoring mode, neither the peak-meter on the master track nor the Control Room’s one work when in record or input monitoring, but they work in play mode or when I switch off the DM mode.
I believe there is a preference under VST- Metering called “Map Input Bus Metering to Audio Track (in Direct Monitoring)” - you may want to verify that it is checked.