Scoring is not exact and sometimes a error

Hello,

I’m making a website for a school where students can try exams before they make the real exam. I want to make this with wp-ro-quiz, it’s perfect for this.

But i have 2 problems. Sometimes the scores are not counted. I made 3 test-quizzes and when i try them, sometimes it lookes like i’ve done a quiz 2 times but i am sure that i’ve done it 3 times, for instance.

The second problem is that i sometimes get the error-message: “De volgende quiz moet afgerond zijn alvorens deze te beginnen:”. I’m sorry, the message is in Dutch, but it says that i have to finish this quiz before i can start another one. And I’m sure it’s finished then.

I use WordPress version 3.5.1 and the latest version of Wp-quiz-pro

http://wordpress.org/extend/plugins/wp-pro-quiz/