Well, I be partially done with that...
The app that opens the media files is Android Open Source Media Player, and is available in all profiles but ONLY opens files in a profile if no any other media player is installed.
The main problem with that is the following:
I have installed Auxio as my media player
I'm using storage scopes iwth that app to only allow to access files at /sdcard/Music
When I try to open a media file in other folder system doesn't detects it and opens Auxio, that isn't capable to access this file.
Is there any way to allow Android Open Source Media Player to open files even if other media player app is installed?