Object Highlight When MouseOver

Hi. Does anyone know what decides if an object is highlighted during game play?
(.GAS) wise?
When I mouse-over an actor (npc or monster), or even armor that can be picked up, the object becomes lite up, or at least no longer affected by surrounding 'moods' and 'lights'.
But some of my mods don't do this and I would like to include it.
Does anybody know what provides this for a game model?

And side question: I know there has been a site change...
Does anyone know why our profile picture keeps being removed?
I uploaded a new one after the change.
And I made sure the size was under 125 as it said.