Ok, I've figured the stuff with the bottles, but there is another bug that spoils everything - I found the room with the spikes. I hanged on the chains as expected. I couldn't find any treasure at the bottom (maybe didn't look enough) and in the room where that trader used to sit also had an empty chest and nothing in it. So, I shoot at the bridge that was connected to a chain, it fell down (yeah, I have my pistol back somehow, the game did not explain, maybe it's another bug). Then I died at the spikes. When I restarted, the bridge is already down. But when I get closer to it and a small cut scene starts, the MC supposed to jump onto the chains. Now, he's missing it and always jumps onto the spikes (probably because of the bridge in another state).