rvt blending not working

Hi. This is my problem nr. 2:
My goal is to blend a mesh to a terrain. I’ve learned that there are many ways to do it, but I cannot get them to work properly. I have my terrain and a mesh representing a stone. I want to use RVT blending following the tutorial at

Before starting the tutorial my scene renders as expected.
Once in the tutorial, I get through step 3 without noticing any problem.
By the end of step 4, the tutorial says “If everything is set up correctly[…] the RVT Volume with the RVT Asset assigned should render correctly. If not, the material will render black.”
It renders black. When I save, it crashes. I have sent the crash report before.
I use a MacBookPro(2020) intel with iris graphics and an e-GPU radeon RX580 (black magic, recommended by Apple).
Any hint is welcome.

MNatiello