Giving learner the choice to submit test score

You have to calculate the test score yourself. Simply have one action for each question. Something like this:

Modify variable: num_right = 0
Modify variable: Add 1 to num_right if Question_0001 Is Correct
Modify variable: Add 1 to num_right if Question_0002 Is Correct
etc.
Divide num_right by xxx (total number of questions)
Multiply num_right by 100 to get %