For Macs: Once you login to the above portal and download the Office 2019 zip file, it will unzip into a folder with two packages, both need to be run for Office 2019 to work.
Office is registered with a serial number, when opening office for the first time, DO NOT SIGN IN, if you sign in, it will wipe the serial number and attempt to register the software with a Microsoft account.
When launching office for the very fist time, just click the small-font option that says "skip" the login. You can then open a new office document.
There is a problem with Microsoft Edge with our website as far as getting the software is concerned.