Need help with inconsistent feeback logic on quiz questions

I am setting up a simple 10 quiz module in Storyline (update 6) and am stumped by the difference in the feedback logic between the multiple choice and multiple response questions.

The client only wants to show feedback if the user gets the question incorrect - this is fine for the multiple choice questions because I have an option to set the feedback by choice. Yeah!

So I am working along and have to add a multiple response question but the feedback by choice option is not available for this question type. I can either have feedback or not. Boo! So I tried just deleting the text in the correct feedback area, but when I preview the quiz question and select the correct answers I get the incorrect feedback.

Can anyone give me help on what I need to do to get the incorrect feedback to display only when the answer is incorrect?

4 Replies