Just curious, what power level are you guys vaping? I'm using a 26g 3.0mm, 6 wrap 1.0ohm coil, trimming the cotton tails to the size of the outside part of the deck, and just stuffing it down in the channels. 3rd airflow setting (I was using the 2nd, but I enjoy the less restrictive lung hit with the extra cotton im using) at around 18-19w after i break the cotton in, and it's working perfectly. (I'm not a high power guy most of the time)
I tried cutting the cotton right to the bottom of the inner build deck keeping the amount at a bare minimum, but it kept flooding as pulling at my normal level was pulling way too much juice in, thus causing flooding and a little leaking out of the afc. With the extra cotton, there hasn't been a drop of liquid in the afc since. when using the minimum cotton, i couldn't even close the juice flow without liquid getting pushed up into the airflow.
Granted I've been pulling a little harder on it just in case the extra cotton stopped air from escaping when juice was pulled in, but I haven't had any problem since I went back to the longer cotton.
Might try going back to my old 2.5 7 wrap 1.0ohm coil, and leaving the tails the same length and see if that works as well. When I first tried that build, I used minimum cotton as I had in my kayfun 4, which led to the leaky problem.