Sorry if that been answered before.
Thank you.
~MAH~
Did you install a custom brush in the ZData\BrushPresets folder? Sometimes that can add a question mark, though I don’t know why.
Which operating system are you running? Is it ZBrush 2018?
ZBrush 2018 on Windows 8.
Despite the fact that “brush” may influence you to consider oil paints and watercolors, Photoshop brushes can go route past mirroring the look of normal media. You can