Menu bars disappearing
Side panels Disappearing
Sometimes you might accidentally close the side panel 'Project Explorer', bottom panel 'problems' or central window. To get these back, go to File > Reset Windows.
Top ribbon disappearing
It is possible to hide the top ribbon by right clicking and selecting 'Hide Toolbar'. DO NOT DO THIS. It is not currently possible to unhide the toolbar.
You will have to install a new Authoring tool and port across all the interventions by copy-pasting them from the broken Authoring Tool's workspace folder to the new Authoring Tool's workspace folder and importing each project into the new authoring tool.