You may try to handle the double click event on the CarouselItem for example:
this.myCarousel.AddHandler(CarouselItem.MouseDoubleClickEvent, new MouseButtonEventHandler(OnDoubleClick), true);
private void OnDoubleClick(object sender, MouseButtonEventArgs e)
//you may implement the logic for opening the required fire in here.
Considering opening different files, you may take a look at this forum thread
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