Index: ps/trunk/source/gui/CGUI.h
===================================================================
--- ps/trunk/source/gui/CGUI.h
+++ ps/trunk/source/gui/CGUI.h
@@ -148,6 +148,12 @@
 	void LoadXmlFile(const VfsPath& Filename, boost::unordered_set<VfsPath>& Paths);
 
 	/**
+	 * Allows the JS side to modify the hotkey setting assigned to a GUI object.
+	 */
+	void SetObjectHotkey(IGUIObject* pObject, const CStr& hotkeyTag);
+	void UnsetObjectHotkey(IGUIObject* pObject, const CStr& hotkeyTag);
+
+	/**
 	 * Return the object which is an ancestor of every other GUI object.
 	 */
 	IGUIObject* GetBaseObject() const { return m_BaseObject; };
@@ -625,8 +631,6 @@
 	 * Map from hotkey names to objects that listen to the hotkey.
 	 * (This is an optimisation to avoid recursing over the whole GUI
 	 * tree every time a hotkey is pressed).
-	 * Currently this is only set at load time - dynamic changes to an
-	 * object's hotkey property will be ignored.
 	 */
 	std::map<CStr, std::vector<IGUIObject*> > m_HotkeyObjects;
 
Index: ps/trunk/source/gui/CGUI.cpp
===================================================================
--- ps/trunk/source/gui/CGUI.cpp
+++ ps/trunk/source/gui/CGUI.cpp
@@ -466,6 +466,28 @@
 	}
 }
 
+void CGUI::SetObjectHotkey(IGUIObject* pObject, const CStr& hotkeyTag)
+{
+	if (!hotkeyTag.empty())
+		m_HotkeyObjects[hotkeyTag].push_back(pObject);
+}
+
+void CGUI::UnsetObjectHotkey(IGUIObject* pObject, const CStr& hotkeyTag)
+{
+	if (hotkeyTag.empty())
+		return;
+
+	std::vector<IGUIObject*>& assignment = m_HotkeyObjects[hotkeyTag];
+
+	assignment.erase(
+		std::remove_if(
+			assignment.begin(),
+			assignment.end(),
+			[&pObject](const IGUIObject* hotkeyObject)
+				{ return pObject == hotkeyObject; }),
+		assignment.end());
+}
+
 const SGUIScrollBarStyle* CGUI::GetScrollBarStyle(const CStr& style) const
 {
 	std::map<CStr, const SGUIScrollBarStyle>::const_iterator it = m_ScrollBarStyles.find(style);
@@ -603,7 +625,6 @@
 	ATTR(style);
 	ATTR(type);
 	ATTR(name);
-	ATTR(hotkey);
 	ATTR(z);
 	ATTR(on);
 	ATTR(file);
@@ -635,7 +656,6 @@
 	bool ManuallySetZ = false;
 
 	CStrW inclusionPath;
-	CStr hotkeyTag;
 
 	for (XMBAttribute attr : attributes)
 	{
@@ -659,9 +679,6 @@
 			continue;
 		}
 
-		if (attr.Name == attr_hotkey)
-			hotkeyTag = attr.Value;
-
 		if (attr.Name == attr_z)
 			ManuallySetZ = true;
 
@@ -679,9 +696,6 @@
 		++m_InternalNameNumber;
 	}
 
-	if (!hotkeyTag.empty())
-		m_HotkeyObjects[hotkeyTag].push_back(object);
-
 	CStrW caption(Element.GetText().FromUTF8());
 	if (!caption.empty())
 		object->SetSettingFromString("caption", caption, false);
Index: ps/trunk/source/gui/IGUIObject.h
===================================================================
--- ps/trunk/source/gui/IGUIObject.h
+++ ps/trunk/source/gui/IGUIObject.h
@@ -428,6 +428,7 @@
 	/**
 	 * Updates some internal data depending on the setting changed.
 	 */
+	void PreSettingChange(const CStr& Setting);
 	void SettingChanged(const CStr& Setting, const bool SendMessage);
 
 	/**
Index: ps/trunk/source/gui/IGUIObject.cpp
===================================================================
--- ps/trunk/source/gui/IGUIObject.cpp
+++ ps/trunk/source/gui/IGUIObject.cpp
@@ -154,6 +154,7 @@
 template <typename T>
 void IGUIObject::SetSetting(const CStr& Setting, T& Value, const bool SendMessage)
 {
+	PreSettingChange(Setting);
 	static_cast<CGUISetting<T>* >(m_Settings[Setting])->m_pSetting = std::move(Value);
 	SettingChanged(Setting, SendMessage);
 }
@@ -161,10 +162,17 @@
 template <typename T>
 void IGUIObject::SetSetting(const CStr& Setting, const T& Value, const bool SendMessage)
 {
+	PreSettingChange(Setting);
 	static_cast<CGUISetting<T>* >(m_Settings[Setting])->m_pSetting = Value;
 	SettingChanged(Setting, SendMessage);
 }
 
+void IGUIObject::PreSettingChange(const CStr& Setting)
+{
+	if (Setting == "hotkey")
+		m_pGUI.UnsetObjectHotkey(this, GetSetting<CStr>(Setting));
+}
+
 void IGUIObject::SettingChanged(const CStr& Setting, const bool SendMessage)
 {
 	if (Setting == "size")
@@ -178,6 +186,8 @@
 		if (GetSetting<bool>(Setting))
 			RecurseObject(nullptr, &IGUIObject::ResetStates);
 	}
+	else if (Setting == "hotkey")
+		m_pGUI.SetObjectHotkey(this, GetSetting<CStr>(Setting));
 
 	if (SendMessage)
 	{