I see how to add item recipes in the ic2.ini, but not sure about adding machine processing recipes.
What i would like to do is make it so if you centrifuge a dust, it gives you a rarer metal output, OR have it output another full dust. The centrifuge takes up so much power, but gives you very little return for the investment. If it doubled the output again, it would be worth the cost to run it. Or if you could output a tiny dust of some other metal that is hard to get, like a nugget of tungsten or something from bluepower, and then remove the ores from world gen.
What I would like to do is make IC2 have a material similar to GTs Chrome, so you can have a high end material that is hard to get and you cannot get it from mining.
Could you make a recipe for the centrifuge where it would take 16 redstone dust and output a nugget of tungsten from bluepower, using minetweaker/modtweaker? Or something like that?