diff --git a/src/Editor/Ghost.Editor/View/Controls/Docking/DockContainer.cs b/src/Editor/Ghost.Editor/View/Controls/Docking/DockContainer.cs
index 792bff7..a5d0b1f 100644
--- a/src/Editor/Ghost.Editor/View/Controls/Docking/DockContainer.cs
+++ b/src/Editor/Ghost.Editor/View/Controls/Docking/DockContainer.cs
@@ -38,6 +38,9 @@ public abstract class DockContainer : DockModule
     /// <summary>
     /// Inserts a child module at the specified index.
     /// </summary>
+    /// <remarks>
+    /// This method does not support reordering existing children within the same container.
+    /// </remarks>
     /// <param name="index">The zero-based index at which the module should be inserted.</param>
     /// <param name="module">The module to insert.</param>
     public virtual void InsertChild(int index, DockModule module)
@@ -101,7 +104,7 @@ public abstract class DockContainer : DockModule
         if (oldChild == newChild) return;
 
         int index = _children.IndexOf(oldChild);
-        if (index < 0) throw new ArgumentException("oldChild not found");
+        if (index < 0) throw new ArgumentException("oldChild not found in this container", nameof(oldChild));
 
         // Detach newChild from its current owner if any
         if (newChild.Owner == this)
diff --git a/src/Editor/Ghost.Editor/View/Controls/Docking/DockGroup.cs b/src/Editor/Ghost.Editor/View/Controls/Docking/DockGroup.cs
index bc0f2f6..5e693ea 100644
--- a/src/Editor/Ghost.Editor/View/Controls/Docking/DockGroup.cs
+++ b/src/Editor/Ghost.Editor/View/Controls/Docking/DockGroup.cs
@@ -11,6 +11,7 @@ namespace Ghost.Editor.View.Controls.Docking;
 public partial class DockGroup : DockContainer
 {
     private const string PART_TAB_VIEW = "PART_TabView";
+    private const string DRAG_DOCUMENT_KEY = "DockDocument";
     private TabView? _tabView;
 
     public DockGroup()
@@ -59,7 +60,7 @@ public partial class DockGroup : DockContainer
     {
         if (args.Tab.Tag is DockDocument doc)
         {
-            args.Data.Properties.Add("DockDocument", doc);
+            args.Data.Properties.Add(DRAG_DOCUMENT_KEY, doc);
         }
     }
 
@@ -73,7 +74,7 @@ public partial class DockGroup : DockContainer
 
     private void OnDragOver(object sender, DragEventArgs e)
     {
-        if (e.DataView.Properties.ContainsKey("DockDocument"))
+        if (e.DataView.Properties.ContainsKey(DRAG_DOCUMENT_KEY))
         {
             e.AcceptedOperation = global::Windows.ApplicationModel.DataTransfer.DataPackageOperation.Move;
             Root?.ShowHighlight(this, e.GetPosition(this));
@@ -82,7 +83,7 @@ public partial class DockGroup : DockContainer
 
     private void OnDrop(object sender, DragEventArgs e)
     {
-        if (e.DataView.Properties.TryGetValue("DockDocument", out var obj) && obj is DockDocument doc)
+        if (e.DataView.Properties.TryGetValue(DRAG_DOCUMENT_KEY, out var obj) && obj is DockDocument doc)
         {
             Root?.HandleDrop(doc, this, e.GetPosition(this));
         }
diff --git a/src/Editor/Ghost.Editor/View/Controls/Docking/DockingLayout.cs b/src/Editor/Ghost.Editor/View/Controls/Docking/DockingLayout.cs
index 0dcd5b4..b76128a 100644
--- a/src/Editor/Ghost.Editor/View/Controls/Docking/DockingLayout.cs
+++ b/src/Editor/Ghost.Editor/View/Controls/Docking/DockingLayout.cs
@@ -76,7 +76,7 @@ public class DockingLayout : Control
 
         if (targetGroup != null && targetGroup.Root != this)
         {
-            throw new ArgumentException("targetGroup does not belong to this DockingLayout");
+            throw new ArgumentException("targetGroup does not belong to this DockingLayout", nameof(targetGroup));
         }
 
         if (RootPanel == null)
@@ -150,7 +150,7 @@ public class DockingLayout : Control
             {
                 // Different orientation, need a new sub-panel
                 var newPanel = new DockPanel { Orientation = orientation };
-                parentPanel.InsertChild(index, newPanel);
+                parentPanel.ReplaceChild(targetGroup, newPanel);
 
                 if (target == DockTarget.Left || target == DockTarget.Top)
                 {