Storyline 360 Unable to Restrict skipping in a quiz

Hi

I have a Storyline 360 Project which includes a Quiz Bank with 230 questions being randomised.

I followed this discussion 

Storyline 360 - Using custom navigation buttons with a quiz review

which included these triggers for this and it worked 

and from 2nd slide:

Now, I need to prevent them skipping questions, I have searched and followed the instructions, e.g. using restriction in the player but trying to make my custom Next button to work with a trigger, isnt working.

Please help, thank you in advance.

Thanks

Margaret