Shift + left click on Ruby (Library> Gemstone> Ruby).
Right click on the part in scene tree, and select "Paste and link material".
You will see Ruby.
Then left double click on the model to open Material Parameter, and change the Material type to "Glass".
You will see Clear glass.
But, cannot assign Ruby to the model again.
I noticed the same issue in all other material.
Is this the issue of "Paste and link material" ?
Yes I noticed that ... copy a material from the library and applying it using "link material" changes the material in the library. Use copy and paste instead.
We will look into it.