I go to My route/more/load route what I would say is the correct way. My kml file is a route in Germany and I am in Scotland. How do I stop the thing calculating from my location in Scotland?

You should disable (via route settings) the start point from being the gps position, and set it as the starting point of the route.

And how would I go about doing that? The only settings I have is delete just before I click to load the route. If I do load is calculates from home.

In the route menu, delete the old one, if you have.
Then, "create route" and set the starting point. Now you can choose the destination (+).
If you want to change the starting point back to the gps position, edit the route via the menu, and tap the arrow at the right, you will be asked if you want to delete the start and turn on the gps receiver.

Ah right. So no way to stop it with my kml files I created in tyre or ITN. I would need to just create routes in the sat nav itself then.

If I open my kml file and save it again it is now saved with a new start point (my location) if I go to edit it then there is no option to move it or delete like I can do with the others.