I think I found the cause. The crap laptop I have here has a problem getting a proper IDX11Device2. Since I didn't even require it to be 2 I replaced that with a plain IDX11Device and it works.
I've uploaded the replaced file to the same link: http://www.georg-rottensteiner.de/files/GDMissileCommand.zip
If you could try to see if that one works that'd be awesome. Thanks a lot!