Landclass autogen

I'm trying to redraw the landclass autogen for a town in Romania. I've redrawn the rivers, roads and main railways so that they are now fairly accurate (using Google earth pic attached). The FS autogen is nowhere near right. When I try to modify the autogen I get this message:'This point is outside the area for Landclass!' Targu Mures - Google Earth my airfield, rivers, roads, railway efforts - Google Earth background my airfield, rivers, roads, railway efforts - FS9 autogenI'd be grateful for advice. Thanks.John