The Prefab tool can be used to create new resources and new BIMs. This tool can be used in two major ways.
BIM Prefab
A BIM prefab is a subset of a larger model, used to either break a large model into smaller more manageable parts, remove sections of the model, or duplicate a single model into multiple copies.
BIM Prefabs must share the same model origin as their parent BIM model, so that the BIM remains geolocated.
Resource Prefab
A Resource prefab is again a subset of a larger BIM model, but this time the tool creates a "Prefab Resource" which can be keyframes and moved dynamically like any other resource from the resource library.
To Create a Prefab first select a BIM, and then make a subselection, either by clicking on elements, lasso selecting elements, or selecting via the BIM Hierarchy, Once a selection is made, a Prefab tool can be triggered via the "Create Prefab" action in the inspector.
This will open the Create Prefab dialog, please give the prefab a name, and thumbnail. You can either leave the pivot of the new Resource at the pivot location of its parent BIM, or you can centre or translate/rotate the pivot to a new location before creating the new prefab geometry when creating a resource. This will make it easier to move and mount as a resource if the parent BIM pivot is far away from the selected objects.
This will trigger Tobe Builder to create either a new BIM or new resource with that name. For BIMs once created they will appear as a new model in the hierarchy, while for Resources, they will appear within the Prefab type in the Library Resource Menu.