Getting a new slotted / drilled carto to wick properly:
This is rather tricky for me, it has to be just right.
What I do is, fill the tank about 1/3 of the way with the carto already inserted, then seal the tank so that the underside of the atty is flush with the bottom side of the tank (so only the atty threading is sticking out).
Then, attach the tank to your PV like normal.
Now, CAREFULLY push the tank down or up until there is a small gap between the top of your PV and the bottom of the tank. The gap should be big enough to slip a standard paperclip into, no more or less than that.
Now, take the mouthpiece off the carto and put three drops in the top of the carto around the sides. Think of it like a clock, put one drop in the 4'oclock position, one in the 8'oclock position and another at the 12'oclock position.
Now, put your drip tip on and seal the drip tip with your lips and (without activating your PV), blow outward for less than a second (as if you were blowing bubbles using only the air in your mouth - do NOT blow from your lungs, just a brief 'push' of air). The goal here is to get the 3 drops to absorb a bit in the wicking material.
Now, without activating your PV, again seal the drip tip with your lips and suck inward as if you are drinking from a straw, enough to 'imagine' your mouth filling with liquid (but in this case, it will fill with air). We aren't breathing air, just sucking EXACTLY like a straw.
If it is extremely hard to suck inward, unscrew the tank from your PV just slightly (maybe 1/8 or less of a turn) and see if that helps. Some older PVs do not have air holes positioned correctly and a small handful of atties are flawed in the same way.
Do this 3 times.
The tank only keeps the atty 'just wet enough' to make it function, but it actually keeps it much drier than you might think when it is functioning correctly.
Take a drag (activate your PV and take a hit). If it works correctly after doing the above, lucky you (but you might have to repeat the above two or three times for continued success).
If it doesn't, repeat the above steps once or twice more, usually I can get a new atty going after 2-3 times of repeating the above steps.
You should not plan to go out anywhere with a brand new atty until you are damn sure it works. You certainly dont want to be fiddling with your PV in public (there are laws against that sort of thing).
Hope this helps.
Oh, and be careful about cutting holes to big on the atty - flooding the atty will cause problems too...