You will need to open the 3D AutoCAD file as an Object in ArchiCAD to be able to see and use the 3D entities.
"File>Libraries and Objects>Open Object..." from the pull-down menu. Then select ".DWG" file type.
David Larrew, AIA, GDLA, GSRC
Architectural Technology Specialist
a r c h i S O L U T I O N S
WIN7-10/ OSX 10.15.7
AC 5.1-25 USA