Counter/Animation

Hello,
I have quite a unique question regarding powerpoint. I'm wondering if it can be done.
I wish to make a marking scheme on powerpoint say for a scenario (eg a test station) the candidate will be scored accordingly if they fulfill certain criteria.
1) It will be in a form of a marking rubric with a box beside each task (eg, introducing one self). If the candidate does it clicking on the box will change it's colour (this is the easy part), the problems I have is rgd part 2.
2) Each criteria is scores variable number of points from 1-4. I was wondering if say 3 boxes are ticked is it possible to display the SUM of the score given to each criteria fulfiled and the corresponding marks.

Example:
Criteria 1: Introduce one self - 1 mark
Criteria 2: Answers question 1 - 2 marks
Criteria 3: Answers question 2 - 3 marks
Criteria 4: Completes task 1 - 1 mark
Criteria 5: Completes task 2 - 2 mark
Criteria 6: Completes task 3 - 5 marks

Say the candidate completes criteria 1,4,6.
The powerpoint should have 3 highlighted boxes and a score of 7. Displayed somwhere.

Can anyone think of how this might be done?

Thanks!