Another thing to consider is the distance between the coil(s) and the center air hole(s). If it's too close, the liquid can create a path into the air hole(s) when you're priming the wick. Once that happens, it will continue to follow that path until you rebuild/rewick or remove the liquid under the coil.
Very true... The Hussar is designed so the coil should sit quite high and well away from the air hole I thought it was very strange when people recommended this...until I built the way it was recommended.
I can't work out why Ken is getting the leaking unless it from filling with juice flow open or a problem with a seal. I do remember reading that a few people had an issue with an O-ring on the first batch of the micro or nano tank. They sent out (free of charge of course) a thicker O-ring to fix the issue.