In my presentation, MoodleMoot2017 (US and Mountain), "Making Boost do MORE", I show how I modify and install my own present file. However, I am not sure if any of this will work for you as you try to work with other presents. I am just offering this to stimulate your thinking. My presentation video is short (< 7 minutes) so it wouldn't take you long to see if anything that I did will work for you. On my web page for this presentation, I do make some comments about Moodle 3.5 updates.