if the game is slowing down / laggy, it can take some time before your mouseclick is registered. If you move your mouse after you clicked and it hasn't registered, it will take the position of the mouse when it finally registers.
I've had something similar where some ships would just leave the gravity using their normal speed (mine were chasing something i believe). brought them back by selecting the ships and telling them to move back to the gravity well.
Couldn't you buff AL culture by giving them a research (tier 5 or so) that makes capital ships into temples of communion (say 0.5 times as strong). This would allow advent to push their culture into an enemy gravity well, or take it along with the ships into the enemy well if he doesn't build enough of his temple of communion equivalent. The coronatas lvl 6 ability could do something similar with the planets it takes over for some period of time,
You can get a a starbase and give it auxiliary government (or non-tec equivalent), and then you can't loose the planet through bombardment -> all the novalith does is wipe out the population, but you keep the planet.
