And yes, it does replace your current install, you can't have 1.4 release and 1.5 daily build running alongside each other (though you can do stuff like install 1.5 daily on Max 2016 and keep 2017 running with the 1.4 release for production work, or similar).
Actually there are ways to do this. :)https://coronarenderer.freshdesk.com/support/solutions/articles/5000577837
1. Install Corona 1.x and then remove (either delete or move) following files: Corona_Release.dll from your 3ds Max root folder