If you experience crashes, try switching from the "Game Ready" driver to the NVIDIA Studio Driver AMD Users:

First, let’s clear up a common misconception. There is no "Service Pack" or "Hotfix" coming from Maxon to make R19 Windows 11-native.

Windows 11 uses a newer driver model (WDDM 3.0+) which can sometimes cause "ViewPort" flickering or lag in older OpenGL applications like R19. NVIDIA Users: