Well, good news, at least--I finally passed this mission...
Yes, for some reason, the Galatea would reach the nav point and spin on its axis for an exorbitant amount of time. Eventually, since I'm in a fighter and I'm attempting to guard a 2 km long ship against an asteroid field, attrition was insurmountable.
Shooting down the bombs was a no-go. From too far away, I couldn't hit their torpedoes (remember I can't target Shivan ships/weapons this early in FS1), and from too close, the explosion obliterated my ship.
I think I invented some new swear words in my five hours of ramming my head against this mission. I patched the game. Nothing. I tried cloning my pilot. Nothing. Then I tried the cheats--just testing things really--and discovered the invulnerability option. Of course, the game won't let me advance the mission with this cheat turned on, but I did discover the Galatea would eventually make the jump, even if it was about ten to fifteen minutes later than originally scripted.
So...well...I cheated. A bit. I used the only cheat that will not forbid mission advancement: unlimited missiles. Unlimited Furies, to be exact. With them, I was able to take down the bombers (since the initial laser weapon does jack against their shields) AND take down each asteroid in about three seconds as opposed to five to six.
Interestingly, the whole experience made me a better pilot. I eventually learned to acquire the target asteroid, and while firing a half-dozen salvos, instead of watching the salvos fire, I was acquiring my next target. I learned to fire the salvos, move on to my next target. and not watch the *oh so pretty even in 2006* explosion.
So, in essence, yeah, I cheated. But is it really cheating when the mission script breaks? Furthermore, I learned a few things about asteroid hunting. I'm reasonably certain this will translate into a better sex life, but I'm still working it out.
Thank you to everyone that posted a suggestion--you have nearly restored my faith in bulletin board communities. Now if I could only find my copy of FS2...
Dobralov