When you recieve a Trade Good in the trade screen from another Civ what exactly happens? Does it go into one of your empty grids on a planet?
I was at war with the Iconians and after I started destroying their military I agreed on a peace treaty if they gave me Xinithium Hull Plating which gave a hitpoint bonus. The hitpoints of one of my tiny fighters was 6hp before and 6hp after I recieved the trade good. Do I need to build it on one of my planets after I recieve it?