Same issue here.European distribution.Nokia cam doesnt work.Nor microsoft cam. Only Proshot external app works. Only when app is closing it says that something is broken but u can open app again and shot without restart.
Well blow me, after 3 months then haven't addressed the issue. IM on the official 1520 update and the camera doesn't work still. Wish I hadn't updated now. Also this typing box doesn't really work on windows phone 8.1 either