I was just looking at the startup screen for Lair and it says this:
DivX video provided by Factor 5 and DivXNetworks
This leads me to believe that something in Lair has used divx, maybe the cinematograhy was all done in Divx, I don't know. Maybe divx is supported only in gameplay but not outside of that. Here a picture of the startup screen.
I attached a screenshot of the startup screen.