In the CMS perspective, adding the Tile navigation component set for a custom tree causes the following error:

Unable to complete your request. The following exception occurred: (Error): Unknown name. .

It is not then possible to add anything else to the canvas, as the same error keeps appearing. To get rid of the error, the browser needs to be reloaded.

See the attached screencast for the steps to reproduce the issue.

The issue is only reproducible in Internet Explorer.