Hhhmmm seems it's not working for the Germans. The US and EU versions are forbidden to be distributed in Germany because they contain symbols which are regarded as unconstitutional (e.g. swastika). For the German version the developers had to remove any appearances of swastikas. Most of them are replaced with an Iron Cross. Additionally in the level "Scuttling the U-529" all Hitler salutes were removed.
I know that the original Commandos game (sold on GOG) does not work on computers set to German. To play them you have to set the region settings in Windows to English or German (Luxemburg). Worth a shot?
[url= http://www.gog.com/en/forum/commandos_series/important_information_for_german_players_of_commandos_ammo_pack ] http://www.gog.com/en/forum/commandos_series/important_information_for_german_players_of_commandos_ammo_pack [/url]
Either that or try manually setting the screen resolution in "unnamedsoldier.cfg " in the \main\configs folder.
The games are known for chucking errors because of screen resolutions.
EDIT: Added link
I've had the same problem with Elite Force II, which I was only able to run on the lowest resolution.
Although, it seems your having trouble with the Quake 3 engine.