CMasking_ID doesn't work with Blend materials?

I’m using Cmasking_ID set to Mat ID and have 3 different blend materials set up, but when rendering the mask they all come out as the same color as opposed to separate colors. All other materials come out fine.

Is this normal or a bug?

Maybe this has something to do with the underlying current issues of the Layered Shader:
https://forum.corona-renderer.com/ Incorrect bump in normals shading AOV in layered material... #msg118241

Any word yet on when all of the issues with the Layered Shader might be fixed?

(internal id=299267305)

This is now fixed in Corona Renderer 5.