Drag and move behind another element?

The front element is a transparent PNG image 

It seems I can't drag through transparent parts of a PNG image

Hello Trevor here is a sample app for this situation:
373 - Drag behind element.zip

In order to move an element behind another and to be able to drag it again after that, you will need a transparent element on top of every element. This transparent element will actually drag itself and the element that should go behind the other element. Thank you for your feedback.

Thanks for that, much appreciated