This was posted on the LOR forum, but it is probably a timely reminder to backup everything at this time of year, regardless of what software you are using. Also, a good reminder to back up all your controller settings, music and video files, and anything else related as well.
If you are new...
From 2016: keithsw1111 first goes through the steps for configuring controllers in xLights 4 and then shows how to map their channels to your various models.