No I don’t create any custom objects.
From C# Grasshopper, Rhino.RhinoDoc.ActiveDoc.Objects retrieves only the objects which are displayed within the RhinoViewport, dismissing all hidden objects.
So I had to run the ObjectEnumeratorSettings, with the VisibleFilter to false, so I could retrieve all hidden objects. From ObjectEnumeratorSettings, I was only able to retrieve objects as an Array, and not as an ObjectTable.
So far I thought that I had to pass by the ObjectTable class to show/hide any objects.
But I just realized that I can just simply set the object’s Visible property to true, even though the SDK only indicates “get”.
So it’s basically solved. Sorry for the confusion.