@fivestar: my experience is that anything in the records folder, no matter the name, will show up in the list of track files in the game, and can be played, if it is a track file.
@general kalle: NTRK is a recording of the actual movements of all the aircraft and vehicles in the mission, and will playback, more or less, correctly, and can also be played, usually, by later versions of the game.
TRK is actually a Single Player or Multiplayer Coop mission file, with the control movements of the player added on to the end. You can check this yourself by taking a TRK file, renaming it with the .mis extension, then put it into a singler player or coop mission folder and open it up in the Full Mission Builder...it's a mission file! Anyhow, these are subject to some errors during playback, and often things will happen quite differently in playback than they did in the actual mission when it was run. Also, typically, TRK files can usually only be played by the same game version they were recorded with. I think there might be some exceptions to what I'm saying here.
Originally posted by dbillo: @general kalle: NTRK is a recording of the actual movements of all the aircraft and vehicles in the mission, and will playback, more or less, correctly, and can also be played, usually, by later versions of the game.
TRK is actually a Single Player or Multiplayer Coop mission file, with the control movements of the player added on to the end. You can check this yourself by taking a TRK file, renaming it with the .mis extension, then put it into a singler player or coop mission folder and open it up in the Full Mission Builder...it's a mission file! Anyhow, these are subject to some errors during playback, and often things will happen quite differently in playback than they did in the actual mission when it was run. Also, typically, TRK files can usually only be played by the same game version they were recorded with. I think there might be some exceptions to what I'm saying here.
A further difference: As the TRK file only contains the start conditions and the player's control inputs (all other inputs being calculated as game AI as if the mission were actually being played for the first time) the file size is quite compact. On the other hand, the NTRK file contains start conditions then position and damage updates for every moving or damaged object in the game throughout the time of the recording. For long recordings it can result in very large file sizes.
Hey Tully......"now there's a name I haven't heard for a long, long time.....young skywalker..."
..<< "99.99% of the world's population believe in luck.... because they do not know the natural laws of Karma and Re-Birth" - Fabian Frederick Blandford 1952 - 20?? >>..
" 'tis all a chequer-board of nights and days, where destiny with men for pieces plays; hither and thither, moves, and mates, and slays, and one by one back in the closet lays" ..The Rubaiyat of Omar Khayyam
I thought that would make the file inacessable. 
Hiya back
