Building a quiz that needs optional graded slides

I have a situation where I need to build a quiz but if possible some of my questions need to be included and graded, or not, based on the answer to another question. Example: The user answers yes or no to a survey question about if their store uses a certain software feature. If they say yes then they are branched to a graded slide that asks a question about that part of the software. If they say no they are branched to the next applicable graded question. I set this all up in quizmaker but then found the grading does not work because even if they answer no and skip over a slide, the system is still figuring that slide into the total number of points for the quiz. So basically if they skip a slide it scores like they took it and answered it incorrectly. I have the full 360 suite. Is there any way to make the scoring work for this scenario?