Same issue with me, on the roof, stuck crashing out when trying to load it. No dice even as admin. Save the TrialOfIronSave line, mine's roughly the same:
ArgumentException: An element with the same key already exists in the dictionary.
at System.Collections.Generic.Dictionary`2[System.Guid,ObjectPersistencePacket].Add (Guid key, .ObjectPersistencePacket value) [0x00000] in <filename unknown>:0
at PersistenceManager.SaveObject (.Persistence persistence) [0x00000] in <filename unknown>:0
at PersistenceManager.SaveGame () [0x00000] in <filename unknown>:0
at GameResources.BuildSaveFile (System.String name) [0x00000] in <filename unknown>:0
at GameResources.SaveGame (System.String filename) [0x00000] in <filename unknown>:0
at GameState.TrialOfIronSave () [0x00000] in <filename unknown>:0
at GameState.Autosave () [0x00000] in <filename unknown>:0
at GameState.FinalizeLevelLoad () [0x00000] in <filename unknown>:0
at LevelStartWrapperExit.Update () [0x00000] in <filename unknown>:0