I can't set a black custom colour.

Now before I say anything else, I /do/ know how to use the Registry Editor and control color command, but I have the same problem with both of them. I try setting them to black and it just reverts to blue. I'll show you the best I can with screenshots, but it might seem fake- Trust me, it's not. Windows is automatically doing this when I choose the colour black.

With SpecialColor:

With control color: