I doubt you will be able to get any meaningful archicad data out of it (or any 3D model at all), it was just a way for clients to explore the model without the need to install software around that time.
I doubt you would be able to do much (or anything) with a current BIMx file in Archicad either.
I would hope so anyway, or I would not be freely sharing our projects this way.
Erwin Edel, Project Lead, Leloup Architecten
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