I've been given a number of STEP files from a client, and am unable to successfully import them in ArchiCAD 21. My process thus far has been this: convert them from STEP into IFC using a third party program (CAD Exchange), opening the IFC file in AC21 using the "General Import" translator, and then saving the IFC file as a GSM object file. When I attempt to place the newly created object, it is both unlike the initial IFC file viewed in AC21 (overly large surfaces and polygons, improperly modelled, etc), and completely bogs down my system, making the use of AC21 impossible. Once the objects are deleted, the project file runs fine.
Have I missed a step, or done something wrong? I'm new to this process, as the Project Manage that used to take care of this is no longer with the company, and the client had sent STEP files to him in the past. We're coming up on a deadline, and I feel as if I'm floundering around. Any help is appreciated, thanks!
Does imported IFC file initially looks OK in ArchiCAD (before saving it as GSM object)?
If yes, the problem can be in high complexity of 3D model when all data instead into one GDL script.
Try to hotlink PLN file into project instead of using GSM. I assume it's archive models of surrounded buildings?
You also can try to safe by parts - for example external walls only, structural slabs and columns only. Maybe it will work better?