My iMac with El Capitan partially downloads Libre Office, then stops. How do I restart the download from the LibreOffice main Mac download site? My first two efforts have been unsuccessful. Thank you.
My advice would be to restart the download from the beginning again.
Without more information all I can suggest is that your internet comms link might not be reliable enough to sustain the size of download.
Be warned however that are several reports here of LO-Base problems with OSX10.11- search for El Capitan in the forum and take the advice about having the correct JRE/JDK