I use a soaked brush of iso 91%, box upside down and brush it out as I normally would. Paying particular attention to the bars. If you do it regularly, it comes off pretty easy. Then a quick burn off.
As for cure and dryness. If you want a quick way, to remove water moisture. Place your herbs in a glass jar, seal it and stick it in the refrigerator. Leave it however long, just make sure the condensation has formed on the glass. Dump your herb out. Let it and the jar normalize to room temp. Do it again, if you want. Until its the dryness you want. With this newest box, I don't have even a hint of the past build up, below the trench, on other boxes.
Is basically a cheat quick cure, which I had to do with some very fresh green stuff. Lost some of the bouquet... But it works just the same.