only add Neutral player if it doesnt exist in the map definition.

OpenRA.Editor/Form1.cs

@@ -377,6 +377,7 @@ namespace OpenRA.Editor
 						using (var eld = new ErrorListDialog(errors))
 							eld.ShowDialog();
 
+					if (!map.Players.ContainsKey("Neutral"))
 						map.Players.Add("Neutral", new PlayerReference("Neutral",
 							Rules.Info["world"].Traits.WithInterface<CountryInfo>().First().Race, true, true));
 					

OpenRA.Editor/OpenRA.Editor.csproj

@@ -90,6 +90,9 @@
       <DependentUpon>PropertiesDialog.cs</DependentUpon>
     </Compile>
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <EmbeddedResource Include="ErrorListDialog.resx">
+      <DependentUpon>ErrorListDialog.cs</DependentUpon>
+    </EmbeddedResource>
     <EmbeddedResource Include="Form1.resx">
       <DependentUpon>Form1.cs</DependentUpon>
     </EmbeddedResource>