Hi Linda,
That doesn't look like an OS compatibility error. It is one we have seen a fair bit and which we believe is related to network security blocking the setup.exe from accessing the download URL.

Most people seem to have luck just pasting the URL which the installer reports failing to download into their browser. Browsers seem to be able to download the Skyline.application file without issue and then the installation can continue from there by running the Skyline.application file itself.

Hope this also works in your case, but let us know what you see trying that.

--Brendan