Can Alt-I also set "Ignores Clip Cubes" state for text and dims and arrows, please?
I'm not sure whether this is a small bug or simply the way different 3D entities export. I've inserted some test renders which show triangulation lines/marks on the ceiling. The ceiling was created using a covered polyline which then had cylinders removed using add void to create the recessed downlight slots for lighting.
The covered polylines with voids create the anomalies in the 3D surfaces when rendered. However, if the polylines are exploded to polygons prior to export then they render okay (images without marks). Similarly, if the 3D entities are modelled as slabs with voids added, then they too render okay.
It appears there is some issue with how covered polylines export? Can this be looked at for future upgrades?