After a very long time, there is an updated version of the Exchange Plugin, which is a free add-on for ArchiCAD 12 and Cinema4D (R10.5 or 11), for Windows and OSX. It replaces the deprecated MaxonForm and allows you to combine work from ArchiCAD and Cinema4D in two major ways: render your ArchiCAD project in Cinema4D and update the geometry from ArchiCAD embed freeform Cinema4D geometry as GDL object inside ArchiCAD and even update them again in Cinema4D There have been long complaints about the combination of both, so I hope they finally got it right with this update. http://www.graphisoft.com/products/archicad-solutions/cinema4d_download.html
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