[LE] What's wrong with this .nif?

[ElfyPers0n]

I edited a Whiterun house mesh to make a cleaner and more generic looking cabin mesh, but every time I try loading it in the CK it crashes. Any ideas what might be causing this to happen?

 

Here's the file: https://drive.google.com/open?id=0ByQECnFP8q9rMUxmRWNJMnRyRUU