You have a flawed library you try to export - i am pretty sure you hit the same errors on smb. the sourcefile "http:" is just invalid. Imo not nfs related. (all other files are written fine as it seems from the log).
AppleTV4/iPhone/iPod/iPad: HowTo find debug logs and everything else which the devs like so much: click here
HowTo setup NFS for Kodi: NFS(wiki)
HowTo configure avahi (zeroconf): Avahi_Zeroconf(wiki)
READ THE IOS FAQ!: iOS FAQ(wiki)
