could you send the IFC also to Solibri's support. AC 15 has a new way of exporting openings of curved walls. Opening geometry is not very good. This could be a similar case. We would like to investigate this.
Matti - I think i know the curved-wall opening geometry issue you are talking about, its similar to the extruded geometry problem in my post above? Also an image of this issue in AC15 attached - FYI all those dark transparent elements are extruded opening geometries created by opening objects and Solid Element Operations, the geometries bear no relationship to the holes/penetrations they should represent
This seems like really poor QA of the IFC export by Graphisoft. I do not understand how things like this keep making it through into releases given how much they are pushing the whole IFC 'OpenBIM' thing. They really need to make sure their IFC export does not have major bugs such as this.