Ok, it's Saturday! I can mess with SE4 ALL day!
Sinapus, I started a new high tech game, maxing everything, except 3 planets. I used 2 races, a 'new' player(mine), and Mephs Earth Alliance from 1.60 (I did not install that, just added the dsgname file, empire, and race stuff).
In the EA AI files, I changed only the fighter Min speed from 6 to 2 and Desired speed from 6 to 16 in the EA DesignCreation.txt file. I disabled all the create random neutral and random computer races options. I started the game.
I did nada, turn one. I checked the EA after the first turn. They had no fighters but were building some CLs and a CVL.
I reset them to computer control and clicked through 5 turns. I checked them again. They had a a carrier loaded up with 32 heavy fighter 2s and a bunch more fighters on the main planet.
So the AI is building the little buggers.
Last night, I ran the Abbidon for about 30 turns and they never built any, however they did design a heavy fighter and (oddly) redesign it, {the same???!!!}, and set the old one to obsolete, hmmm.
So maybe the problem is in the AI files.
The Abbidon just seemed to like super monitor hulls, not unexpected, but, at least while I was messing with them never did build a fighter. hmmm.
The base bridge thing I have never seen. I am going to try and figure that one out next today.
I am not so wedded to the multi-targeting on/in them anyway, if it is causing problems such as you note I'll probably just remove that ability.
It does sound like you may have found a bug. I doubt that any ability should or was intended to over-ride the 'one only' limit, at least for bridges.
Let me know if you find any other interesting
behavior. Thanks again.