Oh, I'll look into it. Interesting point, thanks a lot!
If you look closely at the results of Maptools you see a questionmark in every single line. This means the language version of your windows is not compatible with the language this map was made in/for. Other than changing the regional settings of your windows installation I do not know any solution for this.
Yes, that is exactly the problem. Changing the Windows language settings for non-Unicode file names solve the problem. Thanks again for the help, Willem1974!