[Puke]

answers in no particular order:

Devnullicus, the original compiler of the mod, put it together from his own work and the work of several others back in the old days of SE4, maybe three or four years ago (man ive been playing this game a long time). They are not arround so much anymore, and the mod is currently being maintained by Rollo and some others. In general, it is openly available to use for whatever you want, as long as you give credit where its due. There should be a text file along with the mod, or perhaps a modinfo file that details whom is responsible for what.

No, you cant give negative movement to a component. you can simulate external mount weapons by using some or all of the following ideas: make them smaller, and one shot. make them have less hitpoints. make them 'damaged first' like armor, so they will be ripped of in the first few shots. make them very small, but put a one-component-per-ship restriction on them.

Yes, there was once an effort at making an honor harrington mod. it simulated missiles with various warheads by making really small drones with really small components. it didnt work to well when there were alot on the screen, and combat tended to crash. there was also drone-launch management problems. I tried something similar in my Grit-Tech mod (never finished it, tho) but I just used regular seekers and gave them different stats and had complex tech requirements for integrating various warheads with various seekers.

The example you give of an external mount seeker, is generally considered the best way to do it. I like the idea of adding the ability "is damaged before all other components" since the thing is bolted to the outside of the hull, but thats just me. no one else seems to like that idea.