Is anyone having trouble getting material instance parameters working? Wondering if this is a user error or a bug.

I'm following the documentation, but can't get the "unreal_material_parameter_diffuseboost" param values to transfer over like in the example. My material instance is being created fine, however.

https://www.sidefx.com/docs/houdini/unreal/materials.html#instances [www.sidefx.com]

Following up with a visual example.
The material instance is created correctly and I have some parameters with my vex along side. Why doesn't this work like it's quoted in the docs?

"To change a custom My Color Vector parameter that you created in your material, add a unreal_material_parameter_mycolor detail attribute, Float with a tuple size of 4, and set its value to the desired color value, ( 1.0, 0.0, 0.0, 1.0 ) for a bright red"