Your questions were not numbered, but I'll try and answer them in the order they were presented:
1. YES
2. Go to Preferences/Player, and be sure upmix/resample are not checked, and un-check everything in "Sound Effects", but if you prefer logarithmic volume it's fine to check that. In Equaliser/DSP uncheck any effects. Do NOT enable replay gain.
3. Keep the MB volume control at max, and instead control volume from the system volume panel, or with a tool like Volume2 (
https://github.com/irzyxa/Volume2).
4. YES as far as bass.dll resampling formats it is told your device does not support.
5. There is no "console" way to visually confirm what is going on.