Interactive slide with variables and layers

I've created an interactive slide where the user can drag 2 multimeter leads to test voltage on different wires.  I have a variable set with a total number and depending on where they drag the lead, will add a number to the variable and then a certain layer will show on based on the total.  

The problem is, it keeps showing one layer no matter what they drop it on, even if the variable doesn't change.  I cannot figure out what I am doing wrong!  I have reviewed all of the variables, triggers and layers multiple times and it still won't work.  Trigger is set to show layer when variable changes with condition if the variable total equals a certain number.  Any advice to give?