I have problems with InDesign CS6 (Version 8.1) and Mac OS X El Capitan (version 10.11.2). I have updated both InDesign and Mac OS to the latest versions but still InDesign closes down unexpectedly several times per hour + often the text on a page gets invisible until you scroll up and down a bit. What should I do? I can not use cloud-versions because my major client do not work with them.
As pointed out over and over again here CS6 has reached EOL and is not supported under El Capitan.
Go back to your prior O/S if CS6 is an essential part of your workflow.