Comment 1 for bug 657330

I see 2 problems in that log:

[Debug 15:49:58.446] [PluginManager] Processing config file for "Docky.Core,1.0".
[Error 15:49:58.447] [SystemService] Error in RunOnThread: Operation is not valid due to the current state of the object
[Debug 15:49:58.464] [SystemService] at System.Linq.Enumerable.First[String] (IEnumerable`1 source, System.Func`2 predicate, Fallback fallback) [0x00000] in <filename unknown>:0
  at System.Linq.Enumerable.First[String] (IEnumerable`1 source, System.Func`2 predicate) [0x00000] in <filename unknown>:0
  at Docky.PluginManager.ParseAddinConfig (Mono.Addins.Addin addin) [0x00000] in <filename unknown>:0
  at Docky.PluginManager.<Initialize>m__4D (Mono.Addins.Addin a) [0x00000] in <filename unknown>:0
  at System.Collections.Generic.List`1[Mono.Addins.Addin].ForEach (System.Action`1 action) [0x00000] in <filename unknown>:0
  at Docky.PluginManager.<Initialize>m__47 () [0x00000] in <filename unknown>:0
  at Docky.Services.SystemService+<RunOnThread>c__AnonStorey38.<>m__5E () [0x00000] in <filename unknown>:0

Which probably led to the actual crash:

System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.
  at System.Collections.Generic.Dictionary`2[Mono.Addins.Addin,System.Collections.Generic.Dictionary`2[System.String,System.String]].get_Item (Mono.Addins.Addin key) [0x00000] in <filename unknown>:0
  at Docky.DockletTile..ctor (System.String addinID, Docky.Items.AbstractDockItemProvider provider) [0x00000] in <filename unknown>:0
  at Docky.DockletTile..ctor (System.String addinID) [0x00000] in <filename unknown>:0
  at Docky.ConfigurationWindow.<RefreshDocklets>m__23 (System.String id) [0x00000] in <filename unknown>:0
  at System.Linq.Enumerable+<CreateSelectIterator>c__Iterator10`2[System.String,Docky.DockletTile].MoveNext () [0x00000] in <filename unknown>:0
  at System.Linq.Enumerable+<CreateConcatIterator>c__Iterator1`1[Docky.DockletTile].MoveNext () [0x00000] in <filename unknown>:0
  at System.Collections.Generic.List`1[Docky.DockletTile].AddEnumerable (IEnumerable`1 enumerable) [0x00000] in <filename unknown>:0
  at System.Collections.Generic.List`1[Docky.DockletTile]..ctor (IEnumerable`1 collection) [0x00000] in <filename unknown>:0
  at System.Linq.Enumerable.ToList[DockletTile] (IEnumerable`1 source) [0x00000] in <filename unknown>:0
  at Docky.ConfigurationWindow.RefreshDocklets () [0x00000] in <filename unknown>:0
  at Docky.ConfigurationWindow.OnPageSwitch (System.Object o, Gtk.SwitchPageArgs args) [0x00000] in <filename unknown>:0
  at Gtk.Notebook.SwitchPageSignalCallback (IntPtr arg0, IntPtr arg1, UInt32 arg2, IntPtr gch) [0x00000] in <filename unknown>:0
   at GLib.ExceptionManager.RaiseUnhandledException(System.Exception e, Boolean is_terminal)
   at Gtk.Notebook.SwitchPageSignalCallback(IntPtr arg0, IntPtr arg1, UInt32 arg2, IntPtr gch)
   at Gtk.Application.gtk_main()
   at Gtk.Application.Run()
   at Docky.Docky.Main(System.String[] args)