It may be necessary to clear your user setting and return to the default options. This can be effective for removing the auto-login option.
Navigate to your systems local application data directory. Replace the username portion in the following address with yours to find your local application data directory.
Here you will find a directory named 'The_Vitruvius_Project'. Delete this directory to clear your settings. Do not delete the directory named 'The Vitruvius Project' without the underscores. This will result in the need to reinstall the application.
Once you have deleted this folder all settings will be returned to default the next time the application is opened.