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I am trying to display the ad in the middle of an image based slideshow. It will have multiple images and the ad will be inserted at interval of 5 slides (5, 10, 15 etc..). But I am not sure at how will my code know that all the banners are displayed and can display 6th slide. I could not find any option to add call back URL or even call back function which can be initiated once all the banners have been displayed. Any inputs? Suggestions?