I need help with the "Put a Ring on it" achievement which is about having your capital on a Ring World. How exactly do I do that? I thought you are stuck with your Capital being on your Home World (Starter World)? Is it possible to move your Capital to another Planet? I know the Empire Complex can't be built on anything other than your Civ's Capital World which far as I can tell can only be your Starting World. You can build Planetary Capitals (buildings) on other planets but that doesn't seem to be what triggers the achievement.