Index: Core/Gui/src/Core.Gui/GuiCore.cs
===================================================================
diff -u -r0fe90cd590613f74567c85622bbd2235419a5d5f -r3a27be199e6082eee7cd89141fb8fcadd2cc0b7c
--- Core/Gui/src/Core.Gui/GuiCore.cs	(.../GuiCore.cs)	(revision 0fe90cd590613f74567c85622bbd2235419a5d5f)
+++ Core/Gui/src/Core.Gui/GuiCore.cs	(.../GuiCore.cs)	(revision 3a27be199e6082eee7cd89141fb8fcadd2cc0b7c)
@@ -490,7 +490,7 @@
 
             mainWindow.InitializeToolWindows();
 
-            foreach (StateInfo stateInfo in Plugins.SelectMany(p => p.GetStateInfos()))
+            foreach (StateInfo stateInfo in GetStateInfos())
             {
                 mainWindow.AddStateButton(stateInfo.Name, stateInfo.Symbol, stateInfo.GetRootData);
             }
@@ -729,6 +729,11 @@
 
         public List<PluginBase> Plugins { get; private set; }
 
+        public IEnumerable<StateInfo> GetStateInfos()
+        {
+            return Plugins.SelectMany(pluginGui => pluginGui.GetStateInfos());
+        }
+
         public IEnumerable<TreeNodeInfo> GetTreeNodeInfos()
         {
             return Plugins.SelectMany(pluginGui => pluginGui.GetTreeNodeInfos());
Index: Core/Gui/src/Core.Gui/IPluginsHost.cs
===================================================================
diff -u -r434415295de74c310ce6d3cdd0100c28838cf9ea -r3a27be199e6082eee7cd89141fb8fcadd2cc0b7c
--- Core/Gui/src/Core.Gui/IPluginsHost.cs	(.../IPluginsHost.cs)	(revision 434415295de74c310ce6d3cdd0100c28838cf9ea)
+++ Core/Gui/src/Core.Gui/IPluginsHost.cs	(.../IPluginsHost.cs)	(revision 3a27be199e6082eee7cd89141fb8fcadd2cc0b7c)
@@ -46,6 +46,11 @@
         IEnumerable GetAllDataWithViewDefinitionsRecursively(object rootValue);
 
         /// <summary>
+        /// Retrieves all the <see cref="StateInfo"/> defined on the configured plugins.
+        /// </summary>
+        IEnumerable<StateInfo> GetStateInfos();
+
+        /// <summary>
         /// Retrieves all the <see cref="TreeNodeInfo"/> defined on the configured plugins.
         /// </summary>
         IEnumerable<TreeNodeInfo> GetTreeNodeInfos();
Index: Core/Gui/test/Core.Gui.Test/Forms/MainWindow/MainWindowTest.cs
===================================================================
diff -u -r8339a812e145eab080917a65ceb6d27472b7c076 -r3a27be199e6082eee7cd89141fb8fcadd2cc0b7c
--- Core/Gui/test/Core.Gui.Test/Forms/MainWindow/MainWindowTest.cs	(.../MainWindowTest.cs)	(revision 8339a812e145eab080917a65ceb6d27472b7c076)
+++ Core/Gui/test/Core.Gui.Test/Forms/MainWindow/MainWindowTest.cs	(.../MainWindowTest.cs)	(revision 3a27be199e6082eee7cd89141fb8fcadd2cc0b7c)
@@ -447,7 +447,7 @@
 
                 // Assert
                 Assert.IsInstanceOf<Gui.Forms.ProjectExplorer.ProjectExplorer>(mainWindow.ProjectExplorer);
-                Assert.AreSame(gui.Project, mainWindow.ProjectExplorer.Data);
+                Assert.IsNull(mainWindow.ProjectExplorer.Data);
 
                 Assert.IsInstanceOf<Gui.Forms.PropertyGridView.PropertyGridView>(mainWindow.PropertyGrid);
                 Assert.AreEqual("Eigenschappen", mainWindow.PropertyGrid.Text);