Why isn't Ten Thumbs registered after I enter my registration code and restart the program?
If you entered you registration code for Ten Thumbs Typing Tutor, saw this dialog but Ten Thumbs was not registered after you quit and restart then you did not install Ten Thumbs using an account with full administrative privileges.
Ten Thumbs needs full read/write permission to save your registration information and student progress. Just log in as a user with full administrative rights and reinstall Ten Thumbs. Registration should then work properly.