diff --git a/src/Main/Base/Project/Src/Project/AbstractProject.cs b/src/Main/Base/Project/Src/Project/AbstractProject.cs
index 74b1e70504..d44e292bc3 100644
--- a/src/Main/Base/Project/Src/Project/AbstractProject.cs
+++ b/src/Main/Base/Project/Src/Project/AbstractProject.cs
@@ -362,6 +362,15 @@ namespace ICSharpCode.SharpDevelop.Project
 			return FindFile(fileName) != null;
 		}
 		
+		Dictionary<string, FileProjectItem> findFileCache;
+		
+		internal protected void ClearFindFileCache()
+		{
+			lock (SyncRoot) {
+				findFileCache = null;
+			}
+		}
+		
 		/// <summary>
 		/// Returns the project item for a specific file; or null if the file is not found in the project.
 		/// This member is thread-safe.
@@ -370,12 +379,21 @@ namespace ICSharpCode.SharpDevelop.Project
 		public FileProjectItem FindFile(string fileName)
 		{
 			lock (SyncRoot) {
-				return Linq.Find(Linq.OfType<FileProjectItem>(this.Items),
-				                 delegate(FileProjectItem item) {
-				                 	return FileUtility.IsEqualFileName(item.FileName, fileName);
-				                 });
-				// return this.Items.OfType<FileProjectItem>().Find(
-				//			 item => FileUtility.IsEqualFileName(item.FileName, outputFileName));
+				if (findFileCache == null) {
+					findFileCache = new Dictionary<string, FileProjectItem>(StringComparer.InvariantCultureIgnoreCase);
+					foreach (ProjectItem item in this.Items) {
+						FileProjectItem fileItem = item as FileProjectItem;
+						if (fileItem != null) {
+							findFileCache[item.FileName] = fileItem;
+						}
+					}
+				}
+				try {
+					fileName = Path.GetFullPath(fileName);
+				} catch {}
+				FileProjectItem outputItem;
+				findFileCache.TryGetValue(fileName, out outputItem);
+				return outputItem;
 			}
 		}
 		
diff --git a/src/Main/Base/Project/Src/Project/Items/ProjectItem.cs b/src/Main/Base/Project/Src/Project/Items/ProjectItem.cs
index 10a412b4d8..34554ee11a 100644
--- a/src/Main/Base/Project/Src/Project/Items/ProjectItem.cs
+++ b/src/Main/Base/Project/Src/Project/Items/ProjectItem.cs
@@ -95,6 +95,10 @@ namespace ICSharpCode.SharpDevelop.Project
 		internal BuildItem BuildItem {
 			get { return buildItem; }
 			set {
+				if (project is AbstractProject) {
+					((AbstractProject)project).ClearFindFileCache();
+				}
+				
 				if (value != null) {
 					virtualMetadata = null;
 					virtualItemType = default(ItemType);
@@ -143,6 +147,10 @@ namespace ICSharpCode.SharpDevelop.Project
 			}
 			set {
 				lock (SyncRoot) {
+					if (project is AbstractProject) {
+						((AbstractProject)project).ClearFindFileCache();
+					}
+					
 					if (buildItem != null)
 						buildItem.Include = MSBuildInternals.Escape(value);
 					else
@@ -371,6 +379,11 @@ namespace ICSharpCode.SharpDevelop.Project
 				if (fileName == null) {
 					lock (SyncRoot) {
 						fileName = Path.Combine(project.Directory, this.Include);
+						try {
+							if (Path.IsPathRooted(fileName)) {
+								fileName = Path.GetFullPath(fileName);
+							}
+						} catch {}
 						fileNameCache = fileName;
 					}
 				}
diff --git a/src/Main/Base/Project/Src/Project/MSBuildBasedProject.cs b/src/Main/Base/Project/Src/Project/MSBuildBasedProject.cs
index ef5940206d..00f6d437f3 100644
--- a/src/Main/Base/Project/Src/Project/MSBuildBasedProject.cs
+++ b/src/Main/Base/Project/Src/Project/MSBuildBasedProject.cs
@@ -713,6 +713,7 @@ namespace ICSharpCode.SharpDevelop.Project
 					items.Add(CreateProjectItem(item));
 				}
 			}
+			ClearFindFileCache();
 		}
 		
 		void IProjectItemListProvider.AddProjectItem(ProjectItem item)
diff --git a/src/Main/ICSharpCode.SharpDevelop.Sda/Src/SharpDevelopHost.cs b/src/Main/ICSharpCode.SharpDevelop.Sda/Src/SharpDevelopHost.cs
index 43e5261a99..ba3d8893b3 100644
--- a/src/Main/ICSharpCode.SharpDevelop.Sda/Src/SharpDevelopHost.cs
+++ b/src/Main/ICSharpCode.SharpDevelop.Sda/Src/SharpDevelopHost.cs
@@ -284,13 +284,13 @@ namespace ICSharpCode.SharpDevelop.Sda
 		}
 		
 		/// <summary>
-		/// Event before the workbench has been unloaded.
+		/// Event before the workbench starts running.
 		/// </summary>
 		[SuppressMessage("Microsoft.Naming", "CA1713:EventsShouldNotHaveBeforeOrAfterPrefix")]
 		public event EventHandler BeforeRunWorkbench;
 		
 		/// <summary>
-		/// Event after the workbench has been unloaded. Occurs on the thread
+		/// Event after the workbench has been unloaded.
 		/// </summary>
 		public event EventHandler WorkbenchClosed;
 		
diff --git a/src/Main/StartUp/Project/Dialogs/SplashScreen.cs b/src/Main/StartUp/Project/Dialogs/SplashScreen.cs
index 6b33220428..c6e7400bf2 100644
--- a/src/Main/StartUp/Project/Dialogs/SplashScreen.cs
+++ b/src/Main/StartUp/Project/Dialogs/SplashScreen.cs
@@ -25,6 +25,9 @@ namespace ICSharpCode.SharpDevelop
 			get {
 				return splashScreen;
 			}
+			set {
+				splashScreen = value;
+			}
 		}
 		
 		public SplashScreenForm()
diff --git a/src/Main/StartUp/Project/SharpDevelopMain.cs b/src/Main/StartUp/Project/SharpDevelopMain.cs
index 3f05424e09..30b1f5a838 100644
--- a/src/Main/StartUp/Project/SharpDevelopMain.cs
+++ b/src/Main/StartUp/Project/SharpDevelopMain.cs
@@ -131,6 +131,7 @@ namespace ICSharpCode.SharpDevelop
 				host.BeforeRunWorkbench += delegate {
 					if (SplashScreenForm.SplashScreen != null) {
 						SplashScreenForm.SplashScreen.BeginInvoke(new MethodInvoker(SplashScreenForm.SplashScreen.Dispose));
+						SplashScreenForm.SplashScreen = null;
 					}
 				};