Can't work

[wangzy88]

I use Maya2013 export ASCII format fbx file,but when I run unity throw a NullReferenceException:

NullReferenceException: Object reference not set to an instance of an object
FBXImporter.Connections () (at Assets/Scripts/UnityFBXImporter-master/Source/FBXImporter.cs:959)
FBXImporter.ParseFBX (System.String path) (at Assets/Scripts/UnityFBXImporter-master/Source/FBXImporter.cs:199)
FBXImporter.ImportAllFBX () (at Assets/Scripts/UnityFBXImporter-master/Source/FBXImporter.cs:83)
FBXImporter.Start () (at Assets/Scripts/UnityFBXImporter-master/Source/FBXImporter.cs:44)

I use Unity 4.6.3.