I took a quick look at your application. I saw this nesting structure: While loop - While loop - Event structure
What you should have is the two while loops in parallel. ie While loop While loop - Event structure To terminate both parallel loops simultaneously, give the stop button its own event. I don't know what you mean by the switches not operating. - If you can change the values, but nothing happens, then your event structure is not active. i.e. the while loop the event structure is in has already terminated - If you can't change the switches, then your front panel is locked because an event case is still executing.
