Thank you for the question Skyfaller, I guess I do need to clarify.
What file must I edit to use this? BWD's?
What you edit is any "GPS.d" referance in the PRJ, it is located above the name and MEK file name of any targetable mech on a hex editor.
What it looks like is kinda like this on a hex editor "GPS . d . . . x . x . " Where "x" stands for a certain character. The first "x" refers to a MEK file, the second refers to the chassis.
Do I need special command line arguments to use this?
No, all this list is on the text file is just the codes you would replace in a GPS.d to play as a certain chassis. (e.g., you would just look at a aerotech code and say "okay, so that is the code I'll be inserting over the current GPS.d referance to play as this aerotech.)
Which versions of MechWarrior support this?
ALL MW2 games referance different BWDs even thought the codes may be the same. As far as I know, this is only accurate for MW2:31cc, not GBL or Mercs, they will refer to different mech/vehicle/aerotech chassis.
But to answer your question, these codes were proven accurate for the Pentium edition of 31cc, I am not sure if it will work on Titanium or the Battlepack versions, but feel free to give it a try, they should work.
Will controls really work in the expected manner, i.e., can I fly an aerotech controlling roll/pitch/yaw/speed?
I regret to anounce to everyone that you will NOT be able to control an aircraft by the means of either roll or manual pitch. Basicly it works the same way a mech works, except you can't go in reverse. Your aircraft will always fly at a fixed altitude, so if you start at the hieght of say... 65 meters, and begin to fly over the top of a hill, the aircraft will ALWAYS be 65 meters over the top of whatever it is flying over. So again, it's a fixed altitude.
Thank you again for your question!