My post to the author's github revealed that the files are written to the actual /tmp
directory relative to your hosting or webserver? I'm not sure exactly but, in addition, the files are hidden through Unix because of a precursory '.'
The data is literally being written to /tmp - if you're on a mac or linux machine, you can see these files by opening terminal and running:
ls -la /tmp/
Alternately, you can set $queueDir to whatever you want in the script.
I was able to find them by using putty.