January 25, 2017 at 2:31 PM #19 Correct, you'll need to set up the controller in ES as well. Kodi mappings are for Kodi only.
April 1, 2017 at 9:54 AM #21 You can install the Steam Controller Driver LibreELEC addon from repository, configure it in the UI, and then the Steam Controller works nicely. Well done!