To Attach an iModel as Reference

Select Attach iTwin tool (Drawing > Collaborate > Collaboration > Attach iTwin drop-down)).

The Attach iTwin as Reference dialog opens.

Select the desired iModel to download from the Listbox and click the corresponding Download button.

Note: The first time you attempt to download an iModel, you will be asked to sign-in to your IMS account.

Click the Attach button to attach the iModel once the iModel is downloaded.

You will see all the models available in the latest version of the iModel in a model-tree.

Select the model(s) from the model tree.

Click Attach.

The selected models are attached and you can see the referenced design geometry in the DGN.