Corel Painter Values Jump from 20 to 0 Regardless of Colour Profile, Why? And is There a Fix??

I've always noticed people using photoshop seem to have better-looking values than me and recently I figured it out. Years ago like many of you I learned to change the default colour profile to one that allows full black, HOWEVER, I recently noticed that while you can see all the values in the colour picker, wether your pasting in a photo selecting the painter UK background colour or actually painting, if you use a 0-255 value under 20 it will just show as 0, there is no gradient between 0 and 20 so almost 8% of the value range is lost. I've tried every combination of colour profiles, rendering intent etc, but none in corel painter can get values between 0 and 20, it just jumps, If I use the same settings in photoshop its completely fine and has the full value range. I haven't been able to find anyone talking about this but I have this problem on multiple devices and multiple versions so I doubt its just me, but I dont understand how such a fundamental flaw could exist for so long.

This image shows some low values in photoshop on the right copied and pasted into corel painter on the left where immediately the values under 20 are crushed to 0, the same happens when painting or doing anything in painter it's not just an issue with copy/pasting things.

This is the colour profile I was using in both painter and photoshop for this test there are many combinations of rendering intent and colour RGB profile that will get the same result with a few simply like the default simply cutting off the values at 20ish never even getting to pure black 0.

If your monitor is badly calibrated and it crushes low values you wont be able to see these but here is another painter left photoshop right example 

This screenshot shows that you can select a value between 0 and 20 and it will show in the colour picker as a value between 0 and 20, it doesnt jump around there, but then if you paint with a value under 20 it just shows as full black 0. I can't paint like this, it's such a critical error there are whole genres of painting that are made redundant by loosing out on the lower 7.8% of values, if anyone has any info on this that would be amazing, thank you.