when it is working if you move the mouse pointer until it is over a
note head in the music the pointer changes to a hand-pointer after a
momemnt and then a popup gives the text of the link "textedit://..."
giving the name:col:line of the LilyPond file that has been typeset.
A video in which you can see the mouse doing point and click is at
https://vimeo.com/manage/videos/66885520
towards the end - at 4mins in. (I notice that on this video the mouse
doesn't hover long enough for the popup to happen after the pointer
changes to a hand pointer, but the click moves the cursor in the
Denemo
Display window to the note concerned.)