If you find that the tank leaks out of the air holes after refilling, the problem is that you're pressurizing the tank when you screw the top cap back on. The easiest way to resolve this is to turn the tank upside down before you open the flow control. That lets the pressure out without forcing juice into the well.
I'll try that. I also dialed down the juice flow to about 1 3/4 turns open instead of closer to 2, though I'm using 70/30 to 80/20 VG/PG juice. I'm not sure what is best there, but I understand that 1-2.5 rotations is a typical range - depending on the thickness of your juice.
I've also raised my coil above the build deck airhole a little more, to help keep juice from leeching off the coil/wick into the airhole. I'll see how all that works.