Afternoon, It seems this is due to a issue relating to the enforcement of acceptable violence level.
In Germany they are requried to censor blood/gore and it appears to enforce that if we have a german IP, the bottom line is; game no worky 'auf englisch'!
Big phat topic can be found on Steam forums here, no fix at present it seems:
http://forums.steampowered.com/forums/showthread.php?t=1529626
I certainly hope Bethesda can work with Steam on this to swiftly close this issue.