That gasket is an insulator between the center post (positive) and the outside of the connector body (negative) ...it is there to keep the two seperate and keeps juice from going below. The juice is drawn up through the center of the center pin...through that little hole. it is not uncommon for a little juice to end up in the drip cup. That is what the drip cup is for....catching excess juice that comes out of the atties or cartos. Most often times, it is drawn back up into the atty upon the next draw. You may want to use the blind squonk method to add a little more juice to your carto if it feels dry.