No, the scoring is set based on the harmonized checklist which cannot be modified, but as a country administrator you can change each question to higher weight (anytime).
(Score is set on the chapter level and each question has the weight of importance which affects the chapter score and can be changed anytime, but only increased not decreased.)
How to do it?
Put more importance/ score on a question = change the answer group. That will affect the score of the audit.
If you hide some questions, on the administrator view they will have a bit lighter colour as inactive. However, you can hide them by using Hide hidden questions button. In any case those questions will be not displayed for auditor view.