Notes about the NAS file extension:
Incorrect file associations could be the result of underlying issues within your PC system. As such it is highly recommended to
scan your PC for invalid registry entries, unused processes and other unfavourable system settings to identify slowdown issues.
The NAS file type is primarily associated with 'Nasal' by Andy Ross.
Nasal is a language written for use in a personal project.
It is a small-but-complete embeddable scripting languages. It is still young and incomplete in a few places, but is under active development and has been integrated as the extension language for the FlightGear simulator.