Hi Bani,
I don't have the "Show older apps' check box" on my version and on https://helpx.adobe.com/creative-cloud/kb/creative-cloud-apps-download.html , it's said that Extendscript Toolkit CC is not compatible with macOS X > 10.11.5 ; is the project deprecated. Have you any information about a release's date compatible with last version of Os X?
Regards,