How to play original Bluray discs from XBMC in Linux?

Hi all,

I've a HTPC with kubuntu and XBMC and I play with no problems MKVs and ISOs from my own blurays (created with Windows in other computer)

Now I have install a Bluray reader with the aim of playing my blurays directly, and I've found it doesn't work (The ISO file works, but original disc doesn't).

¿Hoy can I enable the play of those original optical disks? I've try installing an addon called "makeMKV" but when I try to use it gives a message saying something like "MakeMKV doesn't work, it is installed?"

¿Can someone lend me a hand? I would like to play original BDs in the easyest possible way, as I play ISOS now.

Many thanks in advance