If you are using any caching plugin on your site or caching on your server it may take time for the cache to renew and display quizzes. This may cause plugin not to load properly, jump from one question to another, or redirect to a home page.
To fix this you need to simple Clear/Purge all caches and try again. If you still see the issue try flushing your browser cache and check again under incognito window.
To ensure this won't happen again exclude plugin pages and slugs from caching: /wpquize/, /wpquestion/, /wp-personality/.