I and licensed user, but cannot download from the site. is it Nuget only?
Yes, your understanding is correct that NuGet is now the only way to have Aspose APIs. The reason is that we have discontinued the Downloads section. Now the releases are downloaded from NuGet and Maven repositories. Single click and download ZIP file will not work. You can download individual APIs or see the latest release notes at https://downloads.aspose.com/.
You may visit the URL https://www.nuget.org/packages?q=aspose to download the latest versions of Aspose APIs.