On first installation of Editor 32 bit with Facebook installed looks corrupted:

To repro:
1. Install Unity Editor 32bit and Facebook Target support 5.6b10.
2. Open Editor.
Actual result:UI looks corrupted (fonts are red colored and not in places).
Errors in logs:

Missing built-in guistyle In BigTitle
UnityEngine.GUIUtility:BeginGUI(Int32, Int32, Int32)
UnityEditorInternal.VisualStudioUtil:FindVisualStudioDevEnvPaths(Int32, String)
UnityEditor.EditorAssemblies:ProcessInitializeOnLoadAttributes()

Unable to find style 'CommandLeft' in skin 'DarkSkin' Layout
UnityEditor.Toolbar:OnGUI()
UnityEditorInternal.VisualStudioUtil:FindVisualStudioDevEnvPaths(Int32, String)
UnityEditor.EditorAssemblies:ProcessInitializeOnLoadAttributes()

NullReferenceException: Object reference not set to an instance of an object
UnityEditor.DockArea.OnGUI () (at C:/buildslave/unity/build/Editor/Mono/GUI/DockArea.cs:279)
UnityEditorInternal.VisualStudioUtil:FindVisualStudioDevEnvPaths(Int32, String)
UnityEditor.EditorAssemblies:ProcessInitializeOnLoadAttributes()

NullReferenceException: Object reference not set to an instance of an object
UnityEditor.Toolbar.get_lastLoadedLayoutName () (at C:/buildslave/unity/build/Editor/Mono/GUI/Toolbar.cs:230)
UnityEditor.Toolbar.DoLayoutDropDown (Rect rect) (at C:/buildslave/unity/build/Editor/Mono/GUI/Toolbar.cs:550)
UnityEditor.Toolbar.OnGUI () (at C:/buildslave/unity/build/Editor/Mono/GUI/Toolbar.cs:358)
UnityEditorInternal.VisualStudioUtil:FindVisualStudioDevEnvPaths(Int32, String)
UnityEditor.EditorAssemblies:ProcessInitializeOnLoadAttributes()

After first build of standalone for Facebook, problem is gone.