Agustin,
The reason that's happening is because the uploaded files aren't file-storage objects but learning objects (acs_object subtypes). I was using file-storage UI to browsing the content repository items I just added.
In a more design note, learning objects are stored in the file-system instead of the database. Since learning objects could easily be a 80MB video file, if it is stored on the database and many students on a class want to access it simultaneously, pulling such file out of the DB would be rather intense and hit performance pretty hard. Therefore, LORS doesn't provide the option to store them in the DB.
What you can do is to change the code so instead of adding the files as learning object type, to be file-storage types. Have a look at lors::cr::add_folder and lors::cr::add_files (modify/change lors__new_lo / lors__new_lo_version for the file-storage equivalent).
Maybe it would be a good idea to have the option to create folders and files within the file-storage or any other object subtypes... Hmmm...
Ernie
