3. Many do not have this bilateral agreement and this is one of the causes of passengers not being able to fly. Furthermore, it is a fairly complicated process and the normal check in staff have no clue as to how to go about it and only trained ticketing staff can do that. If you get stuck in an out station obviously it makes it worse than the home station where their own staff is available. IATA has a comprehensive guideline for airlines to use on IROPS.
Narrowseat, was it a US carrier on Star Alliance that your flight was cancelled?