Changing Map resource name

Okay, here is my issue. I have a interior that I am trying to change the resource name on and when i do and ensure the new name (deleting the old name) it then messes up the interior. What am I missing?

EXAMPLE
Resource name - OriginalName (with this file name it works just fine)
Ensure OriginalName (Again interior works as it should)

BUT IF I DO THIS
Resource name - NewName
Ensure NewName
The map spawns but there are pieces of the original map still present blocking certain areas and such.

I have also learned how to combine files into one resource so i am trying to do that without changing the name but it is still causing some of the original map to be present.

Any help is greatly appreciated.