Import von .STEP mit UTF-16 codierung fehler

Ich bekomme einen Fehler wenn ich versuche eine .STEP Datei mit UTF-16 Encoding zu öffnen. Ist das ein Fehler im Coding oder wird UTF-16 nicht supported?

Leider kann ich die STEP Datei nicht mitschicken, da diese rechtlich geschützt ist.

Hier die Fehlermeldung:
Error: UTF-16 to UTF-8 conversion failed because the input string is invalid
UnityEngine.Object:set_name (string)
cadex.UnityModelWG_ProductStructureConverter:SetName (UnityEngine.GameObject,cadex.ModelData_SceneGraphElement)
cadex.UnityModelWG_ProductStructureConverter:Visit (UnityEngine.GameObject,cadex.ModelData_SceneGraphElement,bool)
cadex.UnityModelWG_ProductStructureConverter:Apply (cadex.ModelData_Part)
cadex.ModelData_Part:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_SceneGraphElement:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_Instance:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_SceneGraphElement:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_Assembly:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_SceneGraphElement:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_Instance:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_SceneGraphElement:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_Assembly:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_SceneGraphElement:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.ModelData_Model:Accept (cadex.ModelData_Model/ElementVisitor)
cadex.UnityModelWG_ModelConverter:Convert (cadex.ModelData_Model)
cadex.Unity_ObjectFactoryImpl:Perform (cadex.ModelData_Model,string)
cadex.Unity_ObjectFactory:Create (cadex.ModelData_Model,string)
cadimport:ImportCadData (string,bool,string,single,single,single)
game4automation.CADLink:ImportCadData () (at Assets/game4automation/CADLink/private/CADLink.cs:354)
game4automation.CADLink:ImportCad () (at Assets/game4automation/CADLink/private/CADLink.cs:182)
System.Reflection.MethodBase:Invoke (object,object[])
game4automationtools.Editor.NaughtyEditorGUI:Button (UnityEngine.Object,System.Reflection.MethodInfo) (at Assets/game4automation/CADLink/private/NaughtyAttributes/Scripts/Editor/Utility/NaughtyEditorGUI.cs:179)
game4automationtools.Editor.NaughtyInspector:DrawButtons (bool) (at Assets/game4automation/CADLink/private/NaughtyAttributes/Scripts/Editor/NaughtyInspector.cs:188)
game4automationtools.Editor.NaughtyInspector:OnInspectorGUI () (at Assets/game4automation/CADLink/private/NaughtyAttributes/Scripts/Editor/NaughtyInspector.cs:52)
UnityEngine.GUIUtility:ProcessEvent (int,intptr,bool&)