When I open the CSV I exported from Chirp with Libre Office Calc, it puts all the cells in column 1 for all the rows.
This means your spreadsheet is not using the comma character as the separating value (or is trying to do fixed-width columns) and is definitely not going to work. When I open a CHIRP CSV file in LibreOffice it just does the right thing, so I'm not sure why yours doesn't. However, on the prompt you get about how to interpret the text data, you should select "comma" and de-select "tab", "semicolon", or any others. Set "string delimiter" to the double-quote character. As others have mentioned, I can open CHIRP CSV files in LibreOffice, make changes, save (as CSV) and open/import into CHIRP without any drama. The caveat there is, of course, that the edits you make have to be exact and not break the format, otherwise CHIRP has no way of reading your mind to determine what you *meant*.
Also, you've been saying "OpenOffice" but I hope you're not actually using that and are using it as a general term. The actual OpenOffice has been abandonware for ten years at this point and LibreOffice is its successor. I dunno what its defaults are, or what it looks like when it tries to import text data. If you're looking for help from people, you should probably be using the stuff from this decade.
--Dan