ID 391894 - Duplicate layered materials that are referenced from the Library folder do not render correctly.

Problem summary

When there are more than one layered duplicate material references within the Shader Tree, the material is not rendered.

Customer reported version
modo.13.0v1

Customer reported platform
10.14

Steps to reproduce

1) Launch Modo and create a Sphere Item.

2) Press M and the Polygon Set Material window will appear, set the Name as green and set the Color to a bright green.

3) Go to the Shader Tree and move the green material group in the Library folder.

4) This will create a Group material reference that will render a green sphere. If not you may need to delete the original Group reference and create a new one, you can do this by dragging the Group material from the Library folder above the Base Material.

5) If you then drag the Group material from the Library folder above the Base Material another reference will be created. The references now will not render correctly and the Base Materials colour will be used.

Expected behaviour
The highest materials on the Shader Tree hierarchy should override the lower ones when rendered.

Actual behaviour
Neither reference is being rendered.

Workaround
Unknown.

Reproduced by support

This bug has been reproduced in:
Modo 13.0v1 - Windows 10 - Centos 7 - MacOS 10.13

Modo 12.2v2 - Windows 10

Modo 12.1v2 - Windows 10

Modo 12.0v1 - Windows 10

Modo 11.2v3 - Windows 10

Modo 11.1v1 - Windows 10

Modo 11.0v3 - Windows 10

Modo 10.2v4 - Windows 10 - Centos 7 - MacOS 10.13

Earliest version tested
Modo 10.2v4 - This issue appears to be in all versions of the product.