Hi – Tb does a fantastic job when importing spreadsheet data by dragging in a csv and respecting line breaks in cells.
However, I can’t seem to make the reverse happen – get the line breaks back into a spreadsheet’s cell using a csv generated as described here. Obviously this isn’t Tb’s fault – just wondering if anyone has managed to do it succesfully.
(i’m needing to share WIPs with people who insist on using spreadsheets for things they weren’t designed for.)
You simply need to guard multi-paragraph text with quotes, and escape quotation marks inside the paragraph.
Ah, mea culpa. I need to add @eastgate’s correct description.
For CSV novices, do understand it is a ‘standard’ in name only. Dating from the dinosaur era of computing, may different interpretation of the ‘rules’ exist (usually not stated). Put another way, different apps handle exceptions (e.g. line breaks in ‘cells’ differently).
So some experimentation is needed but my start would be @eastgate’s solution and I’d expect that work in most scenarios. 
I have had some success by using TSV not CSV files. I convert the line breaks to a special character e.g. #### first and then to a replace once the data is in.