Why does deactivating "PRE" in the rack on the mixer not deactivate the "Pre-gain"

In the Cubase mixer the rack that has “PRE” activates and deactivates the filters but not the pre-gain section. They seem to be part of the same rack so why does deactivating “PRE” not deactivate all the settings for that rack?

Deactivating the PRE section in the mixer is just a visual thing.
There are still other places (channel editor, inspector) where you can set the phase, the gain, or the filters. You need to set the gain to 0dB to deactivate it.

Ok thank you. Perhaps there is another way to achieve the same thing. Let me explain. I want to load a VST instrument and use it in my DAW but with the level lower for my mix. Then I want to have that same instance of my VST routed to an output in my control room at the un altered level. The reason is that I like to track with my VST or play with the volume much louder than when the VST is in the mix and I don’t want to change the VST level every time I want to play something on my keyboard. I thought the way to do this would be to use a PRE-GAIN on the channel of the VST and to leave the level of the VST unaltered. I thought that then I could disable it for the cue send routed to my Control Room CUE or even to my MAIN. THis way I thought I could have one level in my mix and another for playback. Do you understand and can you help me figure out how to do it another way? My VST instrument is very loud and I like to turn it down in my mix so the levels are at around -12dbfs but this becomes too soft in my CR output and I don’t want to load another instance of the same VST with a different level.

Every CUE send has it’s own mix!

For that I use the L (listen) function on each track (add the button on tracks in project window) and setting the listen level in control room.
Increasing the pre gain is not the correct way because it can alter the sound (i.e. if it goes through a compressor). Anyway you can disable pre gain with the R (read buton) in the corresponding pre gain automation lane.

Yes but if my VST instrument has a pre gain of -10 then the 6 db I get from my cue mix is not very helpful because I would need more gain to get the signal to the same level it was before reducing it in the VST instrument or by using pre gain on the channel

I never wanted to increas the pre gain anywhere, I wanted to reduce the pre gain on the VST channel instead of lowering it in the VST instrument to give me a better level for my mix. I then wanted to use the original un altered level from my VST instrument for my tracking or when I need to go back to my piano to play something. If I have my instrument at -12 it is right for my mix but not for playing back

if you have your mix with pre gain to -12 and you turn it to 0 then you are increasing it, as I said before if you have a track set to -12 pre gain and you compress it then if you set pre gain to 0 it impacts in the compressor performance (it´s just an example, with other effects you may experience differences as well).
That´s why I suggest using the listen option.

If I have my pre-gain set to -12 that is because the VST output is too hot and -12 is a more realistic level so I won’t ever move it back to 0. I only would move it back to 0 for listening myself on the piano as I play but I want the recorded midi to output at -12. If I recorded an acoustic piano it would be at around -18dbfs and to have that level coming from a VST you need to lower the output considerably.

Is the Listen function the best way do you think? Will it give me my 12db (and maybe more if I need) back if I use pre-gain ont he channel?