After destroying a Ferian mine, apparently not all of the miners are redirected to attack the player. They turn hostile, but just sit there doing absolutely nothing.
I've seen this as well.
Need to investigate.
I believe this is fixed in 1.7 Beta 5. I had made several changes to this code and I tested it and it seemed to work fine.
Observed this again in 1.7.
I also noticed that when ordering particularly large groups of ships, that not all of them will follow the order and just drift off into space instead. Since this mostly happens in systems with lots of asteroids and lots of ferians this might be related.
Confirmed.
I found a case in which Ferians were not moving (due to the fact that they don't know how to react to the attackNearestTarget order).
I fixed it so that Ferians without orders join a different colony or gate out.