Can Trade Goods be repealed? If I offer Xinathium Hull Plating to someone but later want to revoke the bonus it gives them, can I? If I am, in fact, trading "goods" and not the technology itself, I should be able to stop sending those goods at any time I please. Will Trade Embargo do this?
You are trading the tech, and as such it cannot be taken back.
Why do planetary improvements of the same kind (e.g. Market Center -> Adv. Market Center) label the button "Build" but from one kind to another (e.g. Market Center -> Factory) label the button "Upgrade"? This seems backwards.
Because they didn't change it until the expansions.
Why can't I launch a troop transport with 0 troops? Let's say I have a planet with a lot of manufacturing capacity so I choose to build the transport on that planet but I want to load troops from another planet. Putting 1 doesn't really hurt, only reducing the local population by 1000, but I *should* be able to launch it empty.
He's the pilot.
It should be possible to move (by "move" I mean decommission and then build on another planet) the four "capital" Super Projects. Any good reason why not?
Because someone would abuse it and they didn't write it that way. It adds depth and requires you to plan things accordingly. This is a strategic game afterall.