The settings defined at IFC Local Preferences (File > Interoperability > IFC) affect the way that IFC data are created and managed.
Save Library Parts Generated During Import To
Set the default location of imported Library Parts when opening or merging an IFC project.
Express Data Manager (EDM) path
The EDM (Express Data Manager) toolkit is the engine which creates an Archicad model from the imported IFC model, and which creates an IFC file out of the exported Archicad model.
During the import-export process, the engine generates temporary files at the path defined here. File size varies depending on model size. Before redefining the path, make sure the selected drive is writable and has enough space.