diff --git a/Editor/TransformWindow.cpp b/Editor/TransformWindow.cpp
index 4378934b9..5ea2a4567 100644
--- a/Editor/TransformWindow.cpp
+++ b/Editor/TransformWindow.cpp
@@ -47,9 +47,11 @@ void TransformWindow::Create(EditorComponent* editor)
 	parentCombo.OnSelect([&](wi::gui::EventArgs args) {
 		Scene& scene = wi::scene::GetScene();
 
-		scene.Component_Detach(entity);
-
-		if(args.iValue != 0)
+		if (args.iValue == 0)
+		{
+			scene.Component_Detach(entity);
+		}
+		else
 		{
 		    scene.Component_Attach(entity, (Entity)args.userdata);
 		}
@@ -253,7 +255,7 @@ void TransformWindow::SetEntity(Entity entity)
 
 			if (hier != nullptr && hier->parentID == entity)
 			{
-				parentCombo.SetSelected((int)parentCombo.GetItemCount() - 1);
+				parentCombo.SetSelectedWithoutCallback((int)parentCombo.GetItemCount() - 1);
 			}
 		}
 
diff --git a/WickedEngine/wiGUI.cpp b/WickedEngine/wiGUI.cpp
index 2465422e3..508d64ddf 100644
--- a/WickedEngine/wiGUI.cpp
+++ b/WickedEngine/wiGUI.cpp
@@ -1620,7 +1620,7 @@ namespace wi::gui
 	}
 	void ComboBox::SetSelected(int index)
 	{
-		selected = index;
+		SetSelectedWithoutCallback(index);
 
 		if (onSelect != nullptr)
 		{
@@ -1631,6 +1631,10 @@ namespace wi::gui
 			onSelect(args);
 		}
 	}
+	void ComboBox::SetSelectedWithoutCallback(int index)
+	{
+		selected = index;
+	}
 	void ComboBox::SetSelectedByUserdata(uint64_t userdata)
 	{
 		for (int i = 0; i < GetItemCount(); ++i)
@@ -1642,6 +1646,17 @@ namespace wi::gui
 			}
 		}
 	}
+	void ComboBox::SetSelectedByUserdataWithoutCallback(uint64_t userdata)
+	{
+		for (int i = 0; i < GetItemCount(); ++i)
+		{
+			if (userdata == GetItemUserData(i))
+			{
+				SetSelectedWithoutCallback(i);
+				return;
+			}
+		}
+	}
 	std::string ComboBox::GetItemText(int index) const
 	{
 		if (index >= 0)
diff --git a/WickedEngine/wiGUI.h b/WickedEngine/wiGUI.h
index 1382ac159..01d9c058e 100644
--- a/WickedEngine/wiGUI.h
+++ b/WickedEngine/wiGUI.h
@@ -280,7 +280,9 @@ namespace wi::gui
 		bool HasScrollbar() const;
 
 		void SetSelected(int index);
+		void SetSelectedWithoutCallback(int index); // SetSelected() but the OnSelect callback will not be executed
 		void SetSelectedByUserdata(uint64_t userdata);
+		void SetSelectedByUserdataWithoutCallback(uint64_t userdata); // SetSelectedByUserdata() but the OnSelect callback will not be executed
 		int GetSelected() const;
 		std::string GetItemText(int index) const;
 		uint64_t GetItemUserData(int index) const;
diff --git a/WickedEngine/wiGraphics.h b/WickedEngine/wiGraphics.h
index 40ab7f0dc..a1e538c36 100644
--- a/WickedEngine/wiGraphics.h
+++ b/WickedEngine/wiGraphics.h
@@ -16,12 +16,9 @@ namespace wi::graphics
 
 	enum class ValidationMode
 	{
-		/// No validation is enabled.
-		Disabled,
-		/// Print warnings and errors
-		Enabled,
-		/// Enable GPU-based validation
-		GPU
+		Disabled,	// No validation is enabled
+		Enabled,	// CPU command validation
+		GPU			// CPU and GPU-based validation
 	};
 
 	enum class ShaderStage
diff --git a/WickedEngine/wiScene_Decl.h b/WickedEngine/wiScene_Decl.h
index 6616f8434..09ec07da1 100644
--- a/WickedEngine/wiScene_Decl.h
+++ b/WickedEngine/wiScene_Decl.h
@@ -5,7 +5,6 @@ namespace wi::scene
 	struct NameComponent;
 	struct LayerComponent;
 	struct TransformComponent;
-	struct PreviousFrameTransformComponent;
 	struct HierarchyComponent;
 	struct MaterialComponent;
 	struct MeshComponent;
diff --git a/WickedEngine/wiSpinLock.h b/WickedEngine/wiSpinLock.h
index 586f2137e..3ffbaaa3c 100644
--- a/WickedEngine/wiSpinLock.h
+++ b/WickedEngine/wiSpinLock.h
@@ -1,5 +1,6 @@
 #pragma once
 #include <atomic>
+#include <thread>
 #include <emmintrin.h> // _mm_pause()
 
 namespace wi
@@ -11,9 +12,18 @@ namespace wi
 	public:
 		inline void lock()
 		{
+			int spin = 0;
 			while (!try_lock())
 			{
-				_mm_pause(); // SMT thread swap can occur here
+				if (spin < 10)
+				{
+					_mm_pause(); // SMT thread swap can occur here
+				}
+				else
+				{
+					std::this_thread::yield(); // OS thread swap can occur here. It is important to keep it as fallback, to avoid any chance of lockup by busy wait
+				}
+				spin++;
 			}
 		}
 		inline bool try_lock()
diff --git a/WickedEngine/wiVersion.cpp b/WickedEngine/wiVersion.cpp
index e50de2a7a..6e85778f0 100644
--- a/WickedEngine/wiVersion.cpp
+++ b/WickedEngine/wiVersion.cpp
@@ -9,7 +9,7 @@ namespace wi::version
 	// minor features, major updates, breaking compatibility changes
 	const int minor = 60;
 	// minor bug fixes, alterations, refactors, updates
-	const int revision = 28;
+	const int revision = 29;
 
 	const std::string version_string = std::to_string(major) + "." + std::to_string(minor) + "." + std::to_string(revision);