Same for me. Since 0.47 (both experimental and stable) in most cases the game crashes when shooting a zombie. While playing 0.47 I've lost 4 charasters in 2 hrs with those crashes. I had a fresh character after every crash. After 0.47 went stable I did not loose my old character on crashes but I can not shoot zombies since the game crashes. Sometime even without shooting, just after some time of playing. Never happened until 0.47. I checked steam files' integrity - it's all ok. 0.47 is somehow buggy. Win Vista SP2, Intel i7 2600k @ 3.5HGz, 8GB RAM, GTX 460. 5TB HDDs.