There are countless other threads here complaining about issues with El Capitan.
That said, you haven't even told us what version of anything you're using.
InDesign CC 2015.1 Release. (18.104.22.168 Build)
The Fiery is for a D700 Xerox with Command workstation 5 (22.214.171.124)
Export a PDF and print that. That’s what you should be doing anyway.
If InDesign crashes, turn off auto hide menu bars in OSX system preferences.