We have a model which when exported to IFC looks like it has been corrupted (although it looks fine in Revit) - floor slabs appear to be moved away from rest of model. File exports with no error messages. We are using IFC to collaborate with Archicad. Can anyone help? See attached image- top right area in view is correct model - bottom left is where IFC has dropped all the slabs (3 different blocks - slabs all above one another) Revit structure 2012