One thing I didn't mention in my previous post was that translations are available in the binaries that I provide but some changes may be needed when building binaries without using Install.sh or BuildBz2.sh. You should call MakeTranslations.sh to create some .qm files, then copy them somewhere the program can find, probably /usr/share/mp3diags/translations.
If the binary is in a folder <bin_folder>, the programs looks for translations in <bin_folder> and in <bin_folder>/../share/mp3diags/translations
If the binary is in a folder <bin_folder>, the programs looks for translations in <bin_folder> and in <bin_folder>/../share/mp3diags/translations