No problem here with the same setup.
So long as you can see the mapped drives in your Windows Explorer you should be able to see them in Archicad.
Personally I don't use "mapped" drives as I don't like locking file paths to a drive letter - it can be different on each machine so publishing path needs to be reset all the time if workin on the same file on different machines.
I use network locations instead which has the full path of the shared network folders.
But I just tried both (mapped and network locations) and they can both be seen in the Archicad open file dialogue.
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