Dear Nicola,
You can read the IES files as simple text files if you need the geometry from them, and visualize that with lines or polygons in the 3d script. When we created our own library parts we’ve found that the inner structure of the available and downloadable IES files are quite different, so we did not implement it – and I’m sure we won’t do it in the near future.
Gergely Fehér
Team Leader, Library Team
GRAPHISOFT SE