Assessment back button issue in Captivate 4

Hello.  I'm hoping that somebody can help us with a back button issue we are experiencing in Captivate 4 assessments.  If we include a back button in our graded assessment there are some problems.  First of all, when we click on the back button to return to the previous question the slide plays straight through without pausing.  There is no problem with pausing the slide the first time through.  This only happens when the back button feature is used.  We also would like the user to be able to click the back button and change their original question answer.  When the back button is clicked all of the answers are greyed out.  Thanks in advance for any assistance you can provide.