Help with triggers/variables: What am I doing wrong?

Looks like you are off to a fun design.

I have not opened your course yet, but from the screen shots you are showing I have noticed a couple of things, so here are my initial observations:

1. Trigger order - You have a trigger to jump to a slide followed by a trigger to adjust the variable. Once the jump trigger happens the second trigger will never happen.  You need to re-order those triggers so that the variable trigger happens first, then the jump.

2. Your trigger to change the  state of your computer screen is "when variable changes".  That can work, but I think there is a more stable solution -  Change the state> of your object>when the timeline starts>of the slide>under the condition> that the variable is true.  

3. Lastly, and maybe most important . . . so I should have put it first.  Based on your design, you are changing the variable immediately when they click the item, and using the variable to then change the state.  If that is your design, you do not need variables, or a state change trigger. Just create a "visited" state of the item.  "Visited" is an automatic state that happens when you click an object - no triggers or variables needed.

Hope that helps