Send a file from server to device

I am using this example by Erel http://ift.tt/1Zgwymg and it works fine in it's original form. I am trying to send a file( a map) to the server (that works ok) do some work on the map and then send it back to the device ... that's my problem sending it back.
I don't fully understand how the example works so i'm 'shooting in the dark', i have searched the forum and tried may different ways but can't send the map back. I was hoping to work this out...

Send a file from server to device

from B4X Community - Android, iOS, desktop, server and IoT programming tools http://ift.tt/1Xl26KF
via IFTTT