Okay, it's a mysterious path problem:
All paths are set to the Sub-folder .\release at the IDE. But with Strg+F5 the program founds only the Sound file, not the others who are in the same folder as the sound file.
If I use 'SetDir' to the Sub Folder 'release' with the media at the beginning - only in the case of the use Str+F5-mode with the help of a code option - the program founds now all files.
Don't know where to hell the problem comes from - but that it founds sound files and images files in the same directory with the same coded paths it's a little bit mysterious.