You might want to chainload ReiNAND through Luma, or at least chainload BootCtr9 through it if you still want to use that. I've heard reports that BootCtr9 is not entirely stable when booting Luma, and Luma sometimes errors as a result. That may have been fixed now, but it was only a few days that I last saw someone post about that.Thx alot!
I think it has something to do with the way it's passing the .firm path to Luma.