This (below) might well be the prime example of someone sneakily filming a game at a presentation. The result is half what appears to be a door, and the game filmed at a 45-degree angle, largely out of focus. We do, however, get to see a gigantic tentacle monster and plenty of other in-game footage. Not exactly super-illuminating for us Witcher-wanters, but a good covert effort from the cameraman. Polygamia, the Polish games site, has an English summary of the presentation here.