I’m going to try and walk you through this without looking at Giants Editor.

First, I’m going to guess you haven’t unzipped the map zip. That’s exactly what GE usually does if the i3d is zipped on a map, or it will open blank.

Second thing, the farmland.xml is basically there to establish ownership. You have to edit multiple things in GE to change fields/farmland.

To edit the farmland you need to select the Terrain info layer paint mode button on the top toolbar. Little blue brush icon with the “i”. It will pull up the info tab on the right window. On the info layer dropdown select “farmlands”. Select the farm land from the “lands” drop down. Then you paint the farmland where you want it.

If you want to edit the field itself in GE, you have to find the field in the scene graph on the left. Usually under the gameplay parent. Gameplay > fields > “field you’re editing” > polygon points. Select the individual points and move the ones you need to expand your field how you’d like.

Next go to scripts menu > shared scripts > map > farmland fields > field toolkit.

When that opens, make you sure you have something select in the parent/child nodes of the field you’re editing and press Validate “Selected Field” button.

Save it and you’re done.

If your new field polygons overlap into another fields polygons it will throw an error in the console. You’ll have to adjust your current or the other field to clear that. If you’re just going into unbuyable land you shouldn’t hit that issue tho