1. Try downloading the newest version (r20.1b) it should be fixed.
2. The black market is the place in the slums below the entrance, and to the right of the Torture Rack & Gentlemen's Club. It has the shops where you can buy Potions, Clothes, Fish, and Junk. I don't think it's ever actually refered to as the 'black market' in game.
Hope I could help : )