You're running out of memory when FFF tries to give Calibre the updated/downloaded epub. I suspect that epub is huge due to images.
The version of Calibre you are using is more than 3 years old and isn't even the last v3 variant. I suggest upgrading using the
official Calibre download.
If you are using Windows and the 32 bit version, I also suggest using the 64 bit version of Calibre instead.
Code:
calibre, version 3.14.0
...
Error: out of memory