Triggers and Conditions

I think part of the problem may stem from using the built-in states.  Try using a custom state.  

Think of each button as two objects.  The shape itself and a completion indicator.   Use a simple shape to indicate Step 1.  Use a second object as a completion indicator (like a textbox) initially set to Normal.  Create a state for the textbox called Complete.  Then group the shape and Textbox.

Repeat for each item in the sequence.

Create a trigger for each group:  Change the state of Text Box to Complete when the user clicks the group

Use a variable on the Exit image to jump to the next slide if all three textboxes are in the Complete state

I added a learner prompt the displays if the learner clicks the Exit image without first clicking all the steps.

File attached.