Hello everybody,
Gilly, your problem is a known bug of CATIA, it was fixed
I think with CATIA V5.7 Serive Pack 4 or 5. Anyway, the way around is to disable the export panel : go to Tools/Options/Compatibility/Iges : disable the export windows. you will be able to export. However, you will still encounter problems with the orientation of the different parts of the model, this is another known bug fixed in CATIA V5.8.
The STEP translator works better and it does indeed import solids but it is way more expensive !!! (the STEP license is darn high !). Some CAD systems like the ones used in the mold industries still work with IGES, so it is important to have a good IGES translator.
Anyway the IGES translator of CATIA is still improving, it is still not at the best level but i've noticed a lot of improvements lately. If you are not satisfied with the product, feel free to contact IBM to complain, the license price is high enough !
cheers