The rewards, as we intended them to be for the release version, were either a credit drop, a free unit, or a damage boost. If it was the credits or the damage boost, it would spawn on the map (typically close to the station) and have a green arrow indicator over it, which then has to be collected by sending a unit near it. Obviously the script that shipped wasn't the one we intended for release, so it may have been a version where the bonus was just automatically applied.