I play the Russian version 0.92. I went through the candle search and the first nightmare, but shortly after I plunged through the house on Sunday, the hammer disappeared from the inventory. I know for sure that I had picked it up the previous night in the African room, but how could it go?! I tried to start the day again and again I got no hammer! What shall I do?

It sounds like you are going to have to patch your game Oranger.

Sue

Hi Oranger, if I remember correctly, you picked up the hammer in your dream!. You will pick one up later in another room.

Upsydaisy is correct, the hammer was only in your dream/nightmare.

But what room? And do I need the hammer again, anyway? I guess yes, because I can't widen the crack in the attic wall with the knife or boring tool. So I took a short tour around the house but found no hammer!

The hammer is in the locked room in the attic. It is the room with paintings.

Thank you! I reckon I must improve the brightness of the screen, for I obviously miss some hints.