I hope I'm at the right place here. I noticed that Libre Office has not specified that it can open CSV files and therefore it does not appear under recommended programs.
I'm afraid I don't know how this works but I guess that would be a rather small fix.
Libre Office Details:
Build ID: 3d9a8b4b4e538a85e0782bd6c2d430bafe583448
CPU Threads: 4; OS Version: Mac OS X 10.10.5; UI Render: default; Layout Engine: new;
Locale: de-CH (en.UTF-8); Calc: group