I too have been looking into these for my coop and had questions. Although you have to work a little to fit the information to your specific need, I thought both of these links were very helpful. Somewhere on the avianaquamiser site is a brief video that shows what causes the leaking(too much water pressure) and a simple fix (a shutoff valve installed upstream of the nipples) that I will be using, but I'm months away from that lol, so I can't show you any pictures yet. ;~)
http://blog.chickenwaterer.com/2012/11/poultry-nipples-and-water-pressure-in.html
http://www.avianaquamiser.com/general/
http://blog.chickenwaterer.com/2012/11/poultry-nipples-and-water-pressure-in.html
http://www.avianaquamiser.com/general/