This was a bit of a head-scratcher.
won’t work. In find(), this is bound to the note that find() is examining. So, this looks for notes that are linked to themselves. We want, instead:
Tinderbox rebinds that, you will recall, to whatever was bound to this outside the find(). expression.
But there was one thing they had forgotten. The need for that was recognized fairly late in the evolution of Tinderbox, and as a result, ^value() failed to set up the necessary mechanisms for using that inside export expressions. This will be fixed in the next update (7.1.1 b266 and later).