in "nhancer" I can see that for galactic civilization 2 dread lords SLI is set to AFR 0x00000001

though you would need to either add DA & TA executables to this profile OR design new profiles for DA & TA

(for reference nhancer is an advanced profile editor for nvidia profiles, much much much more pratical to use than nvidia poorly designed integrated profile editor. And it can be found at : http://www.nhancer.com/)

yes there is, in very late game I get very slight slow downs with a 8800GTS512 @1280x1024 AA4x on immense maps abundant everything with lots of ships orbiting and the mod for increased quality (doh't remember the name but it increase the size of textures for space, planets, & suns

though it is very slight ... so no way near hampering my gameplay experience