I downloaded the MacBook App from the internet but when I load up the app, it firstly wont let me login in. When I select the Character Icon in the bottom left, and select settings, nothing happens. None of those functions work and on the Main screen, this appears. Im running Ventura 13.5.1 M2 Pro MacBook Pro
Yes, unfortunately the new system breaks a bit if you previously had an old (pre-3.0) version of the Supernotes app. Please follow this guide to get everything working again.
Sorry about the inconvenience, this should only be a one-time thing as part of the migration to Supernotes 3 (and offline mode!) In the future, all releases after 3.0 have a much better system for these migrations in place and so this should not happen.