VoxLayer doesn`t work if I try to paint something more complex than just simple shape. I noticed that it happens since later versions of 3D-Coat 2023. After I drew a shape by brush and press "Apply" Coat creates new layer with nothing inside.
Example links:
https://freeimage.host/i/3dcoat-voxlayerbug1.JavAiKv
https://freeimage.host/i/3dcoat-voxlayerbug2.JavApxn