A short while ago I was collecting local radio frequencies by creating a fictitious route in my local area, I the exported the pilot log as a CSV file. Now whenever I reopen SkyDemon I find a grey dotted line with direction arrows on the chart showing the route, how do I remove it please?
I have closed and reopened SkyDemon, tried creating a new route, deleted waypoints and looked through all the menus trying to find how to remove it all without success, any idea please?

As Mike (second Mike) says, you're looking at a NOTAM. You can touch and hold on it, or hover the mouse over it, for more information (or to establish what it is if you've any doubt).

You coul‌‌d turn off NOTAM on the map if you really want to hide it, but it'll go away when the NOTAM has expired. In the meantime you might wish to know there's a formation flight happening along that route.