I had a go, I am using 19.5. I am seeing an issue (that 45 line in the IPR) when I raise substrate roughness (anisotropy is high too). Have had a crash when exiting app, and a crash with IPR on when I set layer opacity to zero.
My machine blue screened today every time I run IPR for more than 20 secs, didn’t happen before with 19.3 (not many tests and simpler material before) also my machine is really old so I don’t trust the hardware.
JD do you have time to share that scene, also curious how much our materials differ.
PS. In this earlier test, the central cap geo on the right torus appears raised, I didn’t move it?