I just discovered a reliable way to crash InDesign CC 2015 every time:
Open an older InDesign file saved in a previous version, so that it opens in 2015 as (converted). Go to Separations Preview and set to Ink Limit. Then open another InDesign document saved in the current 2015 version; instant crash.
InDesign CC 2015
Edit: It will crash until you close the document. So if you open the older file, resave as the current version, and then open another current version document it will crash. If you close the converted file and then reopen, opening other documents is fine.