1. It shouldn't. If it does, there is a glitch in the software.
2. It shouldn't. But the FG prediction is not accurate anyway, so I ignore that. The FG is just a % of the OG and doesn't really take fermentability of the ingredients into account, although it's better than the Beersmith 1.4 version for trying.
For lactose, the Og and the FG are both raised .009 for a pound of lactose in 5 gallons, since it's nonfermentable.