Copied from my qc forum post:
I'd often requested higher precision for all the mouse settings, especially considering many people have very high DPI options on their mice.

As I always remove my config folder for every new build I spotted this input problem immediately and reported it, I hope it will be fixed in the next build asap.

In the mean time you can set any value you wish by closing Quake, and edit:
%localappdata%\id Software\Quake Champions\client\config\input.cfg

The options won't be there unless you changed it in the menu, it gets the option string once you change the value, it doesn't contain anything that's left as default.

So either set the options you want to change to some non zero value in the menu before you close the game, or copy this and edit as necessary, I've edited the values back to the defaults here.

{
"Input": {
"yawScale": 0.022,
"mouseAcceleration": 0.0,
"mouseAccelerationOffset": 0.0,
"pitchScale": 0.022,
"sensitivityCap": 0.0,
"mouseRotateSensitivityCoef": 5.0
},
"cfg_version": 1
}


There is no point in making the file read only as the game will unset this to write to it anyway.

Also they used to store sensitivity (mouseRotateSensitivityCoef) in game.cfg so anyone that lost their setting might still be able to read it from there.

thanks much appreciated but it still seems to reset when i get in game to the closest increment of the slider, it won't save 0.001 as an entry, it will reset to 0.1

before the update I could at least type the settings into the UI but now it just resets them, so frustrating

It will reset if you move the slider/click in the numbers.
So long as you don't mess with them it will keep to the numbers in the config file.
You're safe to go view the menu and change the other settings on that menu page just not sensitivity/acceleration/pitch/yaw that you want taken from the cfg, you can see when you hit save it will change 1.8 to 1.79999934234243434 (made up example) or whatever the float approximation it uses is, but it won't force it to 1.75 or whatever the rounded value of your setting is as touching the setting in the menu would.