Latest oft updates to tavlet show battery volts on screen.
It important battery volts remain over 12v , this applies to any flash system.
Check your oft and obd connections by going into logg screen real time display run engine and wiggle cables and connectors, if it drops out fix the connection problems before trting to flash car again
The obd ports on some early models 2012\2013 are dodgy
More info
http://www.ft86club.com/forums/showthread.php?t=99171