Need Help with Error while replacing original cas room mesh

Hi all! I've been trying to work out how to make a 3D CAS Room with a working mirror. I used littledica's cas room as a reference for finding the .package file data like the instance and type to add to an empty .package however when I try to import my mesh, nothing changes in the preview window on s4studio and in game. Does anyone know what could be the issue?

These are the data files I add to my .package file: Data files added 

And this is the mesh that shows regardless: CAS Mesh


If anyone could help in any way possible, it's much appreciated!