Well,
This one was a bit of a toss up. Lactose does contribute to the original gravity, so I was reluctant to put it in the "Misc" category of ingredients.
However, since it does contribute to OG, then it ends up feeding into the "Estimated FG" which is based on yeast attenuation and not really knowledgable of the ingredients used.
Also, the Estimated FG is really only a guess, since so many other factors enter into it - such as mash temperature, fermentation conditions, ingredients used, etc...
So - I'm not sure how to easily resolve this short of making a special case for the "Lactose" ingredient so it raises the FG estimate.
Cheers!
Brad