Need help extracting 3DS models

[o0DemonBoy0o]

So i'm fairly new too this, so any help would be appreciated. 

I'm looking to get some of the models from the Mii Plaza and its updates. 
While I was able to get most models using braindump, I didn't seem to get anything from any of the updates. 
I managed to get a cia of the 4.0 update but from what I can tell it's encrypted and I have no idea how to decrypt it if even possible.

Another thing is some models don't open properly or at all when using EveryFileExplorer.
Here is an example https://www.dropbox.com/s/5kkbthsydmhofh....cgfx?dl=0