Need help with branching within a quiz in Storyline

Hi

I have created a quiz which requires the learner to click through a series of hotspots to prove they can carry out a task. For the times when there's only one way to carry out a task, it works great, however when there's more than one option, I'm running into three problems, even when I use branching:

1. The learner sees an incorrect feedback message if they pick the second hotspot option.
2. The learner can only acheive 83%, even if they answer everything correctly
3.  When reviewing the quiz, the learner sees the questions in the other branch as well as the branch they followed.

For problem 1, I just hid the feedback for that question, and allocated the same number of points to each answer in the question. 

I'm stumped with problems 2 and 3. I found a tutorial Jeanette produced about using question groups, but I can't see them in Storyline, just question banks. 

What am I missing?

Laura