As Rod points out, you will indeed need a user variable for each score that you want to show later on. He didn't mention that the score for the last submitted question is stored in a reused system variable cpQuizInfoLastSlidePointScored. Because this variable is repopulated after each question, you have to copy its value to a user variable like this:
Assign v_score_x with cpQuizInfoLastSlidePointScored for slide x I labeled the variable v_score_x
As an alternative to having to attach this statement to the action performed On Success and On Last Attempt, I always attach this to the On Enter event of the next slide. Do not forget to attach it also to the slide immediately after the last question slide if you need that score as well?
Lilybiri