Terrain Editor Crash on Start Location Selection

[Recoup]

Hey guys,

I am making a new map for myself and the lady to play on, but for some reason when I select a city and checkmark "Start Location" to confirm it as a starting point, the track appears with a red circle over it and then the editor freezes. I have to Ctrl-Alt-Delete to get out of it but I am unsure of where this error is coming from.

Advice?