After following this thread: Kodi (formerly XBMC) for OMV
It was smothly but when I have to try... I was sure graphics were not going to work at first try but after try lot of things I think that is impossible to make graphics works with this kernel and my hardware.
MOBO: B85M-ITX (Asrock)
CPU: G3220 Intel
Graphics integrated.
I tried everything. I have omv 2.1 whit kernel backports 3.16
Afterall it seems like I will have to choose between NAS and HTPC