3d information MUST be imported into an ArchiCAD OBJECT and then the object placed in the model... You can't import walls, etc. directly into the plan view.
Therefore, it would appear that MEP models will be imported as ONE (really big) Object to be placed into your architectural model. It must then be "aligned" in the 2d and 3d space.
The only importer that attempts this is coming from Sketchup... But in my experience, leaves a lot to be desired (that is import Sketchup Models as ArchiCAD native elements).
I have no experience with ArchiCAD's MEP Modeler.
Duane
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