The Akorn is unlike ceramic kamados. It has a very low thermal mass. It heats up and cools very quickly (internally) compared to ceramic kamados which tend to "soak up" heat energy and release it. This acts like a thermal buffer. The Akorn is two thin metal shells with insulation (probably just air) in between. It is built like an Igloo cooler or a double pane window.
The trick I've discovered is to accurately control how much charcoal is burning at any one time. If you simply dump charcoal into the firebox and light it in one spot, the amount of charcoal available to burn increases as the burn progresses. We get away with this in most other cookers, but the Akorn is uber efficient.
Try the Ring of Fire method shown in this video:
. Basically, I place a metal pail (2.5qt) filled with sand in the middle of the fire grate. This acts to control where the charcoal lives and also to act as a thermal mass. Then I place charcoal around the outside of the pail and light one end. The fire then burns slowly around the ring, keeping the amount available to burn relatively constant throughout the cook.
Another thing I recommend is a ceramic heat diffuser, either the one available from Chargriller, or a home made one like I show in the video.