Cannot install Adobe CS5 - install hangs at calculating time
Had the same hanging problem when I tried to install InDesign and Photoshop CS5 5 on two iMacs (both 24-inch, early 2009 models with 4GB RAM) that I have formatted to install El Capitan.
From a tip I read somewhere, I installed Java that I downloaded from this link: https://support.apple.com/kb/dl1572?locale=en_US
You have to restart the computer after installing Java. InDesign installed without a hitch after that. Photoshop hanged twice on one iMac but on the third try, after another restart, Photoshop successfully installed. 
If this remedy failed, I would have tried the solutions mentioned here: Installation of Adobe Creative Suite 6 hangs at AdobeHelp on Mac OS X El Capitan