@Marian > The Export function is not available if:
you don't have a USB device connected to which you can export
you don't have a playlist selected at the time you go to export on the menu
A .m3u8 file is simply a UTF-8 encoding of an .m3u file. Magic of all things magic, simply rename the file from .m3u8 to .m3u and Traktor will read it.