SOLUTION:

1.) import a part of your map (for example a house) in MED
2.) do some work on vertices when needed, delete surfaces in inner blocks
3.) export to 3ds
4.) load it in Milkshape
5.) select all vertices and do the fat-boy-tool method
6.) reload it in MED
7.) flip normals
8.) do a black skin, save as mdl
9.) reload in WED as mdl. its the same size (a bit bigger caused by the milkshape manipulation) as your originally map part. Pose it and make it passable. NO OVERLAY!!!


Sincerly
Christian Behrenberg

BTW: you mean OUTLINING. Celshading could be done by special painting the textures.