Is it a Renovation Filter problem?
I know there is an issue when exploding DWGs …
https://archicad-talk.graphisoft.com/viewtopic.php?f=22&t=69419&p=308845#p308840
Try changing to a Renovation Filter that shows everything.
(I have no idea if that is the issue).
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11