@David-Howarth In the Page Menu, select ‘Place Waypoint Button”:
You will then see a cursor which you place where you want to insert a waypoint by moving the map and then select the button ‘Place Waypoint’.
I use an iPad for most of my route planning and this stops the inadvertent waypoint insertion when touching the map. You can also use the ‘Lock Waypoints Button’ - See reply below.