In fact I need only few things: year, track, CD, bitrate, and maybe total tracks. All of them (except total tracks) are standard tags in audio files.
they may be "standard tags" as you say ... but WD xml (and in the firmware) is not, and was not coded to include them.
my advice, give up ... there isn't any way to achieve what you want (except for a 'workaround' and using linksheets ... but that will still not give you a "bitrate" of each individual song)
use mediainfo if you want to know the bitrate of a music track