(I'll post this to the list, too. Maybe it contains some valuable hints for other people, too).
You made three mistakes:Hello dear friend Andreas:
Thank you for your help, yes I think that the problems in the Windows version could be for the Direct X and its updates, but the MAC I don't know because it has the same problems that Windows without updated. Here I send you the MAC version for you find one solution.
1) You need to put all data files (including fonts etc.) OUTSIDE of the app bundle. Put all data files to where the app bundle is. Do NOT put them inside of the app bundle.
2) Always use file extensions! Using simply "Melodia" as the file name is a very bad practice. Although most file formats can be recognized easily using header information in the file, this is NOT the case for mp3s. To recognize a mp3 file safely, it requires a lot of work and file parsing. Recognizing mp3s just from the file data really sucks. So to be safe, just name your file "melodia.mp3" ... then the audio system already gets a hint where to start.
3) Even worse, your Melodia file is corrupted. It contains a corrupted ID3v1 tag at the end of the file. According to the standard this should be 128 bytes, but in your file it was only 80 bytes which caused the audio server to reject this file. I've corrected this by simply stripping off the ID3v1 tag entirely. Now it works.
Attached is a fixed version of your program for Mac OS X. This should work. I've now corrected all your mistakes but please note that I normally can't do that because it takes too much of the time that I don't have