3D Coat v.4.9.34: the problem persists.
Blender, Unity, few IDEs: scaling is fine.
Currently I'm refraining from purchasing 3D Coat because of this issue until it's solved.
sprayer,
Ok, now I think I understand why some people don't experience this problem. You have a low UI scale coefficient and a large 4k monitor.
I have high UI scale coefficient and 23" 4k monitor.
3D Coat is able to scale a bit, but is unable to scale more.