Need read first post form Password Protected SAMBA / NFS Shares Kodi+wrapper, to get working...
NFS shares are mounted at /mnt/nfsShare/
Kodi is Root filesystem /mnt/nfsShare/
http://www.futeko.com/newforum/index.php?topic=813.0
You read my mind. Thanks.

Ok, so shares remounted with Q5 Pro, paths mass replaced in Kodi' library (import-export to xml), everything looks great.
Except in the process I realized that it does matter a lot how I configure the linux NFS share, because it needs a specific configuration to not get the same error than before with samba. It must be some kind of sorcery because the configuration change does not seem to be related to the error but well, this is linux again...
NFS config (/etc/export) that gives the same error to internal player than before on Samba:
path 192.168.1.1/24(rw,async,all_squash,insecure,subtree_check)
NFS config that makes internal player works with jelly 200 but makes it unplayable to Kodi's player:
path 192.168.1.1/24(rw,async,no_root_squash,subtree_check)
I feel that I'm almost there...

Unfortunately I'm not a NFS expert so can someone explain/suggest?