King Oz Records VSTplug Governor v1.3 x64 x86 VST WiN [FREE]
x64 x86 VST WiN, 6mb
The VSTplug governor is a basic solution for mastering to meet -6 dbfs standards.
It's a new release and though there is no known issues, it should meet your expectations in regards to being able to mix down to a certain level.
Though it's not entirely accurate in the way of knobs, without adding lufs c-weighting and such it's hard to do. But it works. I hope that's good enough. I plan to attempt to add c-weighting for the dB level, My fear is that it will not be real time, and there will be 20, 30 ms latency.