You can create unlimited quizzes. There are no limitations on that.
WP Quiz will work with any WordPress theme out there. If you are facing any issue while using, please contact us and we will help you resolve it.
Yes, the quizzes created are fully responsive.
Yes, WP Quiz offers one-click demo import data. Just head over to WP Dashboard -> WP Quiz -> Import/Export and click on Import Demo button.
Wath more videos here: Best WordPress Quiz
Read more at https://wordpress.org/plugins/wp-quiz/faq/