It sounds to me like you have a flooded coil on the Nautilus. It can happen if you over primed it or if you're really taking hard draws. The way to clear it is to turn the entire unit upside down and take a medium smooth draw. What this does is keep the wick holes above the juice level and it vaporizes the extra juice. The turn it right side up and you should see a few bubbles as the wick re saturates. You might get a little juice into the mouth but just spit it on a paper towel or bog roll as you all say.
You said you had it on max power. At 30 watts it will burn up the coil and taste terrible. Start low (8 to 10 watts) and take a small hit. bump it up and repeat. If it gets too warm, tastes funny or starts to taste burnt back it down. I usually vaped my Nautilus in the 12 to 15 range for the 1.6 ohm coils. Different juices will have different sweet spots.
With the iStick, click 3 times on the fire button to select watts. Set it at 8 with the arrow buttons and take a hit. To lock the setting in hold both arrow buttons down at the same time (I found using one thumb for both buttons easiest, but it takes a few tries to get it sometimes). If it moves when you are trying to lock it down, reset it and then try again.