The functionality that currently exists within the Markups List to add custom columns is not available in the 3D Model Tree when using the CAD plugin feature to generate a 3D model directly from a Navisworks file. This would be helpful to add custom columns that can be edited in order to assign a "group" name to a collection of 3D items and then be able to sort and filter by those groups (e.g. all pipes currently selected in the model are "Segment A" of my piping network). Essentially I'm just asking for the ability to assign new metadata to objects in the 3D model tree instead of being limited to only what was exported.
Thanks!