Reproduction steps:

1. Open the attached project “TestTerrainShadow.zip“
2. Open the scene “SampleScene“
3. In Assets Window, go to Settings → PC_RPAsset
4. In the Inspector window, enable “Use Rendering Layers“
5. Alternatively, In the Edit → Project Settings → Graphics, disable the Compatibility Mode (Render Graph Disabled)
6. Observe the result

Expected result: In all combinations of disabling/enabling the “Compatibility Mode (Render Graph Disabled)” and “Use Rendering Layers“ there are no issues
Actual result: Terrain is corrupting and no shadows casted, unless “Compatibility Mode (Render Graph Disabled)” is enabled and “Use Rendering Layers“ disabled

Reproducible in: 2021.3.45f1 (see notes), 2022.3.52f1, 6000.0.26f1, 6000.1.0a3

Reproducible on: macOS 14.6.1 (M1 Pro), Windows 11
Not reproducible on: No other environments tested

Notes:

* In 2021.3.45f1, the Render Graph is not present yet, but it seems that the Render Graph may be contributing to the problem where it is available
* Also reproducible in Player
* Not reproducible in an empty project