I dont see the pattern why some names are ok and some are not ok. I thought the space made problem but i tested it and that is not the issue causing problems…
check layout names in rhino and exported dwg from the file, some layout names are without proper name.
cant tell if its problem of autocad or rhino but i think its rhino problem with export.
layout_names_to_dwg_test.dwg (110.5 KB) layout_names_to_dwg_test.3dm (1.5 MB)