Hello mark_pr,
Thank you for submitting a question about using icons and widgets. The menu areas and widget areas are separate. I hope that does not drastically alter your plans. The menu areas are reserved for menus.
It is possible to use shortcodes in widgets in the widget areas by adding some brief code to a theme file. There is a guide in the WordPress codex regarding using shortcode with widgets. This kind of modification falls under the category of general WordPress development. And, this would only work for adding shortcodes to the widget areas as opposed to the menu areas.
I strongly advise making this modification in a child theme so that the changes are not wiped out when the BoldGrid themes are updated.
Best,
Christopher M.