Passing variables between pages

One trick that I have used is to "show" a transparent button over the main page as you leave it to bring up your popup. Have two action on that button: one that says "on-mouse enter" show the "X" or "O" based on the condition of the variable, and the other that hides the button. When the student closes the popup, their mouse cursor is in the button and it will execute your mouse-enter show action, then hide the button again.One trick that I have used is to "show" a transparent button over the main page as you leave it to bring up your popup. Have two action on that button: one that says "on-mouse enter" show the "X" or "O" based on the condition of the variable, and the other that hides the button. When the student closes the popup, their mouse cursor is in the button and it will execute your mouse-enter show action, then hide the button again.