Typically you will not be able to preview (or view in the live event) your booth if all of your items are not associated with a section. If you do not have a section created, make sure to create one and then associate each item with the appropriate section.
If your booth does not appear as expected, either with formatting issues, videos and/or images not showing, or items missing, please review your coding and/or uploaded items and try again. You can also reach out to our support team for further assistance.