Mine

System.TypeInitializationException was unhandled
  Message="The type initializer for 'EditorStock' threw an exception."
  Source="supertux-editor"
  TypeName="EditorStock"
  StackTrace:
       at Application..ctor(String[] args) in C:\Documents and Settings\Arvid\Skrivbord\supertux\supertux-sharp\supertux-editor\Application.cs:line 114
       at Application.Main(String[] args) in C:\Documents and Settings\Arvid\Skrivbord\supertux\supertux-sharp\supertux-editor\Application.cs:line 566
       at System.AppDomain.nExecuteAssembly(Assembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()


{"Okänt bildfilformat"}
   at Gdk.PixbufLoader.Close()
   at Gdk.PixbufLoader.InitFromAssemblyResource(Assembly assembly, String resource)
   at Gdk.PixbufLoader..ctor(Assembly assembly, String resource)
   at Gdk.Pixbuf..ctor(Assembly assembly, String resource)
   at Gdk.Pixbuf.LoadFromResource(String resource)
   at EditorStock.AddIcon(String stockid, IconSize iconSize, String resource) in C:\\Documents and Settings\\Arvid\\Skrivbord\\supertux\\supertux-sharp\\supertux-editor\\EditorStock.cs:line 37
   at EditorStock..cctor() in C:\\Documents and Settings\\Arvid\\Skrivbord\\supertux\\supertux-sharp\\supertux-editor\\EditorStock.cs:line 21