Steeping water for an extract batch? Or are you looking for infusion volume for an all-grain mash?
If the first, then you can steep the grains in the amount of water called for in the recipe. The program does not set parameters on how much of this water is used for steeping.
If the second, then you can set the infusion volume in the mash profile. Edit your mash profile and change either the amount of water added or, to have it scale with your recipes, change the ratio of water to grain in the appropriate box.