What software are you using to communicate with ?
and how ? RS232 ?
In Cimco, it doesn't use the mastercam settings, I'm guessing other software would be the same.
The Xfer settings would need to be done thru the actual software set-up area, something like- create a macine or contoller profile, set your baud, blah blah etc and then save
You open the NC-file with the Xfer software, select a profile, then, "Send to Machine", go to the machine and then "Read" that file into the control.
This is a basic procedure to send the entire file, it may alter slightly for different machines
DNC is a similar procedure, but the machine must be DNC capable before going into this area