Articulate Storyline 2 custom notification message for internet connection loss

Hi Everyone,

My client has requested that a custom message pop up in the event that a user loses internet connection while taking a scorm test on their lms.

I'm aware of this link: https://www.articulate.com/support/storyline/how-to-let-users-know-if-their-course-attempt-cant-be-saved-in-an-lms-in-the-event-of-an-error  

which explains how to implement a notification, but I do not see any way to customize the message that would pop up.  Does anyone have some insight into a possible solution?

I'm using articulate storyline 2.  Attached is the message as they want it to appear.