Milkshape has an option for exporting as .map. You'll have to do quite a bit of tweaking (texturing, setting surface properties for walkable, ect). You can't export the texture, only the mesh as a .map set of brushes. Like I said, Embrace is very tweaky and trying something like this could cause it to crash.
Why does everything has to go through that software
Milkshape and its clunky unstable interface is the reason so many people get turned off from modding this game.

Ok emo moment over, if its possiable to bring in Geometry that way I might give creating a map a shot when I have the time since I have some nice scenes that could make some cool maps in this game.