To import 3D model directly into the design without adding to catalogue, follow these steps
Select Insert tab, and then Import 3D Model icon in the toolbar.
In the window that opens provide a name and choose a placement for the SKU.
To upload the object itself, select the Upload 3D Model button. In the next window, upload the corresponding 3D model (.obj, .blend, .skp or .glb format) and material file (.mtl format)
To add model to the design without adding to catalogue for future use, select Import without checking the box against Publish to catalogue first.
Now, the SKU is added to your design.
To import 3D model to user-only catalogue, follow these steps
Select Insert tab, and then Import 3D Model icon in the toolbar.
In the window that opens provide a name and choose a placement for the SKU.
To upload the object itself, select the Upload 3D Model button. In the next window, upload the corresponding 3D model (.obj, .blend, .skp or .glb format) and material file (.mtl format)
Check the box against Publish to catalogue first, and select Next.
In the next window, Select User Catalogue from the toggle.
Specify the Category, Subcategory, Group and SKU name.
Now, the SKU is added to your design and to your user catalogue.