Hi!
in RC1, Clicking on the Image preview icon does nothing. The same is with the “Hide template” checkbox.
While on the topic, One of the competitors have similar template system. When a template is saved, a screenshot of the container(s) can be auto-generated. I think they are sending the data to their servers for processing. This is a very neat solution. They offer the preview of the templates inside the builder when dragging them into the content. A neat solution. 