Hi sdf16,
first of all, you can deactivate the Boxcryptor tutorial. Yes, it comes back after you fully log out because there is a difference between signing out and exit Boxcryptor.
Signing out deletes all temporarily cached data like to remember to not show the tutorial again.
And I am very sorry but there is no option to hide the green lock icon. I guess you are using very low dpi settings.
Best regards from Germany,
Philipp