Hello there,
You can easily set the selector range by setting the x-axis extremes. I recommend doing this on the chart's initial load event. I have updated the example you provided also disabling the events (let me know if I have understood you wrong) by adding styles to the
highcharts-navigator class as this is the easiest way to achieve that, see:
https://jsfiddle.net/BlackLabel/c0rgau3w/
Let me know if this meets your expectations,
Kind Regards!