kodi 17.3 will not load on mac

I have tried to down load Kodi 17.3 from the Kodi website. Every time the mac verifies the download i get a box that popes up saying ” Kodi file broken move to the trash”. This has happened since i removed 17.1 due to the security issues. Can anybody help me also i am not a wiz on the mac. So easy instructions would help.