I see - and I had the answer right there in front of me as it was just a matter of opening that txt in Sublime just like I did with the OBJ. And indeed opening the .txt in it does recognize the lines/structure.

Interestingly enough opening the .txt in some programs that respect the CSV structure and resaving from there seems to generate a .txt that has lines in notepad while still being a clean CSV. So perhaps it could be possible to write out a structure that does both ? But of course not at the cost of doubling the line breaks.

On a related topic : is there a feature in MOI that would convert shapes (with lines, polylines and curves) to segmented shapes, similarly to what the DXF exporter does to shapes and the OBJ exporter does to filled shapes ? The point (!) being to have points that can still describe the curved elements accurately, without resampling the straight lines. A "convert to polygon" feature of sorts :