A very early mod fix (along with some analysis of what may be wrong with trading) has been released today over at the Egosoft forums, which may go some way towards solving the broken trading in X Rebirth.
via N4G: pc news feed http://n4g.com/news/1402844/x-rebirth-modder-releases-work-in-progress-trade-fix
via N4G: pc news feed http://n4g.com/news/1402844/x-rebirth-modder-releases-work-in-progress-trade-fix