I know this thread is old, however I have found one way to change the main control to temp on the DNA 200 board. I was having the same gripe as many of you, Watts is useless once you set it in temp control. I had the idea to upload a DNA 250 theme into my device, and found one on the Evolv boards designed for the Lost Vape Drone. My screen settings had the temp as one of the smaller texts on the side, but when I uploaded the theme, it somehow converted the temperature to the main adjustment and the watts was one of the small texts instead. I'm sure this can be done with other themes, I have never created a theme so I'm not sure what caused it to change, other than the DNA 250 natively uses temp as the main control once in temp control mode. The screen is fully functional, when I change the temp it is reacting as it would on my DNA 250 mod. Anyone wanting to make this happen can download the Lost Vape Drone theme that is on the Evolv downloads page. Maybe someone can study the theme and figure out what caused the switch, because it is a very desirable thing for the DNA 200 board. Hope this helps anyone who may see this.