I'll take a closer look at the entry. Maybe I missed something important.

This from the FSX SDK:
atc_airline The ATC system will use the specified airline name with this aircraft. This is dependant on ATC recognizing the name. ATC will treat this aircraft as an airliner when this is used in conjunction with atc_flight_number.

If you don't give it a flight number, then the Airline is not mentioned! It must have a Flight Number!

[fltsim.5]
title=CS 767-300 Captain Paint5
sim=B767-300RR
model=rr5
panel=
sound=RR
texture=british
kb_checklists=
kb_reference=
atc_id=N764A
atc_airline=
atc_flight_number=
ui_manufacturer="Boeing"
ui_type="767-300 RR"
ui_variation="British Airways"
ui_typerole="Commercial Airliner"
ui_createdby="Captain Sim"
description="767-300 Base Pack v1.5\n(c) 2011 Captain Sim www.captainsim.com"
ui_wglts=1

So the ones in red test need to be:
atc_airline=Speed Bird
atc_flight_number=767
so that the ATC will call you "Speed Bird 767" and not just "Boeing", or "Boeing 767".

The attached image shows how the ATC responded once I filled in the blanks. ;)

Mark

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