If anyone is interested, I have two freely offered campaign backgrounds/ rules reinterpretations for the FASA game.
One is set on a Colonial Operations Light Cruiser about 30 years before Kirk. By the FASA timeline, this is before Dilithium, and when Transporters had only just been certified for shipboard use. It is also the time of the "Terra Return" movement, so creating some potentially interesting politics, diplomacy and espionage. I have reimagined many of the Branch skill lists, and most of the equipment and tech.
The other is about 15 years before Kirk, and set aboard one of the totally new "Starship" (Constitution) class vessels. I am converting the Four years war into a slower burn conflict, more about colonization and building allies/servitors than an all out war. Branch lists are again modified, as is tech, but both to a lesser degree than the first setting.
I haven't play tested either, since my real life world is way to busy to play, but hopefully these may be of use to others?