Hello everybody.

I was trying to instance (point instancing) a subnet which contains a light and some geometry.
Together they form a lamp rig of sorts (a neon lamp)
Now, I want a part of the lamp geometry inside the subnet to not cast shadows from the light,
and I can set this using the “Shadow Mask” option of the light.
The problem is that this do not work with instancing (or point instancing).
I don't know how to make every instanced light to not cast shadows from it's corespondent instanced geometry.
This doesn't work even if I make a HDA out of this subnet (which is the goal anyway).
Also, It seems that I can't see the contains of the subnet (light OR geo)
in the viewport in case of instancing, why is that?

In the end, the goal is to make a lamp asset (together with light and geometry)
that I can also instance on many points in a scene.
How should I approach this?

Your light model itself is not really physically possible. In the real world that piece of mesh would block a light behind it.

What if you just assigned those cylinders to be mesh lights instead of trying to fake it with that large rectangle?

There is also a special light called a light template that you can assign different shaders for the lighting and the shadowing. Maybe you could replace that rectangle with a template and leave the shadowing shader blank?