@LARdT COPY command in 'tools'
Thank you - that explained what it is for and how to use it.
The option copies a file including it's folder structure from SD Card to Internal Storage or from Internal Storage to SD card.
My copies did not appear until I restarted the ECO Reader.
Then I found many files on both Internal Storage & SD that I had copied when trying to work out what the command did - I always leave my ECO Reader on - never turn it off.