diff --git a/OpenRA.Game/Primitives/SpatiallyPartitioned.cs b/OpenRA.Game/Primitives/SpatiallyPartitioned.cs
index 04013b9c46..8372a74fea 100644
--- a/OpenRA.Game/Primitives/SpatiallyPartitioned.cs
+++ b/OpenRA.Game/Primitives/SpatiallyPartitioned.cs
@@ -31,22 +31,22 @@ namespace OpenRA.Primitives
 			itemBoundsBins = Exts.MakeArray(rows * cols, _ => new Dictionary<T, Rectangle>());
 		}
 
-		void ValidateBounds(Rectangle bounds)
+		void ValidateBounds(T actor, Rectangle bounds)
 		{
 			if (bounds.Width == 0 || bounds.Height == 0)
-				throw new ArgumentException("bounds must be non-empty.", "bounds");
+				throw new ArgumentException("Bounds of actor {0} are empty.".F(actor), "bounds");
 		}
 
 		public void Add(T item, Rectangle bounds)
 		{
-			ValidateBounds(bounds);
+			ValidateBounds(item, bounds);
 			itemBounds.Add(item, bounds);
 			MutateBins(item, bounds, addItem);
 		}
 
 		public void Update(T item, Rectangle bounds)
 		{
-			ValidateBounds(bounds);
+			ValidateBounds(item, bounds);
 			MutateBins(item, itemBounds[item], removeItem);
 			MutateBins(item, itemBounds[item] = bounds, addItem);
 		}
diff --git a/OpenRA.Mods.Common/Traits/World/EditorActorPreview.cs b/OpenRA.Mods.Common/Traits/World/EditorActorPreview.cs
index a2dc3daded..dea7b228e8 100644
--- a/OpenRA.Mods.Common/Traits/World/EditorActorPreview.cs
+++ b/OpenRA.Mods.Common/Traits/World/EditorActorPreview.cs
@@ -167,5 +167,10 @@ namespace OpenRA.Mods.Common.Traits
 		{
 			return new ActorReference(actor.Type, actor.Save().ToDictionary());
 		}
+
+		public override string ToString()
+		{
+			return "{0} {1}".F(Info.Name, ID);
+		}
 	}
 }
diff --git a/mods/d2k/maps/shellmap/map.bin b/mods/d2k/maps/shellmap/map.bin
index 61a628a722..24a300ddbe 100644
Binary files a/mods/d2k/maps/shellmap/map.bin and b/mods/d2k/maps/shellmap/map.bin differ
diff --git a/mods/d2k/maps/shellmap/map.png b/mods/d2k/maps/shellmap/map.png
index 9a5765a445..865d37dc88 100644
Binary files a/mods/d2k/maps/shellmap/map.png and b/mods/d2k/maps/shellmap/map.png differ
diff --git a/mods/d2k/maps/shellmap/map.yaml b/mods/d2k/maps/shellmap/map.yaml
index dbc3feeb51..a5685f89fb 100644
--- a/mods/d2k/maps/shellmap/map.yaml
+++ b/mods/d2k/maps/shellmap/map.yaml
@@ -30,8 +30,8 @@ Players:
 		Name: Creeps
 		NonCombatant: True
 		Faction: atreides
-		Enemies: Atreides
 		Color: EF00FE
+		Enemies: Atreides
 
 Actors:
 	Actor4: spicebloom
@@ -46,21 +46,9 @@ Actors:
 	Actor8: spicebloom
 		Location: 65,64
 		Owner: Neutral
-	Actor26: concreteb
-		Location: 57,58
-		Owner: Neutral
-	Actor28: concretea
-		Location: 54,58
-		Owner: Neutral
-	Actor29: concretea
-		Location: 54,59
-		Owner: Neutral
 	Actor30: wind_trap
 		Location: 54,58
 		Owner: Atreides
-	Actor31: concretea
-		Location: 54,62
-		Owner: Neutral
 	Actor32: silo
 		Location: 54,62
 		Owner: Atreides
@@ -71,15 +59,6 @@ Actors:
 		Location: 54,56
 		Owner: Atreides
 		Facing: 24
-	Actor35: concretea
-		Location: 46,39
-		Owner: Neutral
-	Actor36: concreteb
-		Location: 48,37
-		Owner: Neutral
-	Actor37: concreteb
-		Location: 50,37
-		Owner: Neutral
 	Actor38: palace
 		Location: 50,37
 		Owner: Creeps
@@ -99,7 +78,7 @@ Actors:
 		Location: 46,64
 		Owner: Creeps
 	Entry: waypoint
-		Location: 80, 8
+		Location: 80,8
 		Owner: Neutral
 	AtreidesSpiceRefinery: refinery
 		Location: 57,58