NvRTX_Caustics-5.2 HT mode 2 can't get scene color

I want to use overlay-material as a post-process mask. But the scene color is black.

But it works fine under HT mode 1.

Is it a bug or feature not support?

HT2 mode is the blend mode that mix raytraced translucency with none raytracing support data type like legacy cascade, you should use physical based material parameter rather than translucency overlay scene color. The traditional rasterization translucency logic like camera vector, distance fade, and pixel depth offset etc is completely not supported in raytracing translucency.