The demo site is located at URL http://drupal7quizdemo.dev.knackforge.com/, demo users accounts are below,
HTTP Authentication, username & password - knackforge
Drupal test user accounts,
To avoid security threat the site offers only a limited access to test users. The site will reset itself for every one hour to prevent any misuse by test users. It is recommended to create a new user account to avoid messing up with other test users.
Also the site has been protected by HTTP Authentication, username & password for the same is knackforge.