I did this once, the home system is the Planet nearest to where the freighters are when you buy them. There might also be a slight chance that it is the planet nearest to the civ you bought the freighters from. But when I bought them, both those possibilities were the same planet.
I have never had the alliance option come up in chat with the other races. Even when I was friendly with them, and a alliance would have helped us both. For terror stars you make a star base and then under one of the tabs for the upgrade of the base is a terror star module. As long as you got the tech, I never made one so I don't know what goes on after that point.
I went to my EB on the release day, got the last copy. They get thier shipment around 11am, I was there at 11:45. The one I got was still inside the shipment box. I didn't ask how much they had ordered, but whoever got the copies just pounced on them.
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