Hi,

Fuses and settings are read from a couple of places in the Arduino Ide directory structure.

Look in arduinoide\hardware\arduino for boards.txt and programmers.txt.

If you make changes or additions to these files with Visual Studio or Atmel Studio open you should click "Tools>Arduino>Reload Tool Chain" for the new config to be loaded.

It's possible to create your own boards.txt under a certain directory structure below the SketchBook\Hardware folder. However it's a little more complicated because you would have to alter the "core" property to be arduino:arduino. So initially I would hack the one under the arduino ide folder by adding your own board def of changing an existing one that meets your needs