.I can't get any other themes to do it either. Even ones that have the code put directly into the Column rather than placed in the Global tab.
I don't think you correctly read what you just quoted. What he said is that he uses a custom tag, inside the file. Doesn't matter if the lasttrack code is there if you don't have the tags necessary.
Hmm.. I may have read it wrong, but it did remind me that I could just add a tag to the last track of an album to do the underline. But from what I understand (I'm still really new to this whole thing) there isn't anything in his code that references any other tag other than %tracknumber%.
These are the two lines that supposedly indicate the last track of an album from Kylith's .fcs.
$if($greater($len(%tracknumber%),4),$if($strcmp($num(%tracknumber%,2),$substr(%tracknumber%,4,5)),is_last=1))
$if($strcmp($len(%tracknumber%),3),$if($strcmp($num(%tracknumber%,1),$substr(%tracknumber%,3,3)),is_last=1))