OK I tried a lot of fiddling but it just doesn't work, my approach is this:
Assuming I have a directory with tracks from exactly two different artists:
%_directory%, %wwwpayment% and %wwwpublisher% are set to 'dummy'.
I) IF %wwwpayment% = dummy THEN it is set to %artist%.
II) IF %wwwpublisher% = dummy AND %wwwpayment% <> dummy AND %wwwpayment% <> %artist THEN it is set to %artist%.
Now %wwwpayment% should contain the first artist and %wwwpublisher% should contain the second artist. Thus %_directory% is set to '%wwwpayment% & %wwwpublisher% - %album%'
Unfortunatly something in 2 II) seems to go wrong because i always end up with the respective artist being put into %wwwpayment% AND %wwwpublisher%.
Heres my code for 2b):
Format WWWPUBLISHER tag:
for better reading (unfortunatly the forum cuts the leading spaces...):
The last $not case should make sure the artist is not put into %wwwpublisher% if it is already in %wwwpayment%. I don't understand why this doesnt work.
If someone has a better idea for merging two artists into the directory name i would be delighted to know.