Multiple choice questions with 1 correct answer, but only partial credit on 2nd attempt?

I've created a short quiz to do some testing of Captivate 6 features.  I will frequently be dealing with quizzes that have multiple choice, true/false and matching questions. My sample quiz only has 3 questions; two multiple choice and one true/false. Each question has a value of 10 points. For the multiple choice questions, the user gets two attempts to get it right before they are forced to continue to the next question. True/False questions only get one chance for obvious reasons.  On the multiple choice questions, if they get it right on the first try they should get 10 points, but if they get it wrong and then get it right on the second attempt I want them to get partial credit of 5 points. If they get it wrong twice they should get 0 points and move to the next question. I have the true/false question assigned a value of 10 points with 0 penalty since that one can only be right or wrong in one shot.

I thought that assigning a point value of 10 and a penalty of 5 would accomplish what I wanted on the multiple choice questions, but that's not the case. I was hoping it would subtract 5 points on the first attempt and then add 10 if they got it right the second time. But apparently the penalty only applies to the final attempt. So answering both attempts wrong yields a score of -5 because I answered all 3 questions wrong and came up with a quiz score of -10 (-5 for both multiple choice, and 0 for t/f). All of this stems from the fact that Captivate only scores the final attempt of a quiz question.

So how do I accomplish what I'm aiming for here? I figure it will involve some sort of variables and/or scripting since I want the first attempt to be scored -5, but only if the second attempt is correct (and thus awarded 10 points...minus the 5 deducted for the first wrong answer)...otherwise the score should be 0 if both attempts fail.  Thoughts?