I am drawing some landscape with a largish city in Autocad and now I am trying to build a basic engine to walk about the place. However I am haveing severe problems with exporting it to 3ds using 3D exploration, most of the objects just do not show up in 3D exploration. On another note I tried converting it first in AutoCad to 3ds but it is still not rendering all the objects. If you care to I could try posting some screen shots of what I mean.