The red area is going to be the control section (electrics / timers etc), see post #16
However I am working on another design so that I can have the ballast in the center section but doing that reduces the size of the left compartment, but having that side smaller is no big deal as it will mainly be used for sexing the plants.
If all goes well the control section will be sealed, if it goes bad (heat buildup (which is unlikely)) then I have a solution ready to go....maybe.