Returning to Aurora after a few years I came across this interesting planet. My three survey cruisers found it about four jumps from Sol.
The first problem was the jump point was only 34m k from the cost 0 planet which was defended by 25 orbital bases. They did have an Achillies heel, their missiles were only capable of 24,000k/s, while my fastest was able to go at 55,000k/s. Their energy tech was ahead of mine as they demonstrated when they destroyed one of my survey cruisers with strength 65 energy blasts. They also had 497 fighters which they used to destroy my second cruiser. I was able to kill about 150 fighters before falling to the missile barrage. The third cruiser was also engaged by the fighters but after killing another 120 fighters managed to duck into a newly discovered warp point.
I then blockaded the contact point with my systems. Fortunately they spend most of their mobile fleet trying to break the blockade. I then took 161 20,000 ton cruisers into their system. I attempted to engage their remaining mobile assets and the orbital bases, in that order, a mistake!
All was well until the missile storm came in. Turned out their size 1 missiles, while only capable of 24,000k/s had a range of 102m k. Since I was still sitting on the warp point the fleet jumped out. Leaving most of my missiles dependent on their internal guidance. Most of the 12,000 missiles I had launched were directed at the orbital bases, and while the bases killed many hundreds they could not kill them all and all the bases died. This still left a lot of missiles around the alien homeworld. Unfortunately for the aliens they brought their freighters, fighters and many of their remaining mobile assets to orbit the homeworld, were they died. It was as though I had placed an enormous mine field around their planet. If they had waited three hours the missiles would have self destructed, but they just didn't wait. If they had used their AMMs as AMMs they may well have survived as much of my missile inventory still contained 30,000k/s missiles. After a wait of an hour or so My fleet returned to the alien system and was able to clean up easily.
It was after the conquest of the planet I found the NPR had broken Aurora! I kept getting Populate shipyard Errors, divide by 0 etc. When I looked into it I found the planet had 314 Shipyards with 628 slipways and a capacity of 6,350,000 tons naval construction and 24.510,000 tons of commercial construction. When I looked at what they were building I found they had 160 x 10,000 ton destroyers, 53 x 20,000 ton cruisers, 97 x 30,000 ton battlecruisers, 12 x 50,000 carriers and 188 x 1000 ton FACs under construction in addition to 66 colony transports of 21,300 tons. Fortunately the new ice age caused by the destruction of their ground forces prevented any completing. Had this armada been completed I don't know whether I could have won as only 48 of my 161 cruisers were latest production and all the rest two or three generations old while I had yet to lay down my first carrier. To give some idea of the planetary economy I have under 3000 construction factories and 3000 mines, The aliens had 22,500 construction factories and over 33,000 mines (that's after bombardment casualties) and resources to match, not less than 1.4 million tons, most in excess of 2million tons and duranium being 16 million tons with availabilities to match.
The really sad thing is I fear the game is now broken, cannot get rid of the error message! Part of the problem appears to be that shipyard capacity does not match size of the ships being built. Even after conquest this is a problem.