I only have one rule, after clicking on the node it takes a couple of seconds to pop up but it does find the tracks and although the counter finds them the bar never moves, I will report this as a bug.
http://www.ventismedia.com/mantis/view.php?id=5015

Nyn

Click on the node and after a short time, it shows up, only stating "Reading tracks..." and the progress bar doesn't fill as it cycles through the tracks. Inconsistent Album Art, Dead Links & Unsynchronized Tags all work properly, it's only the Unorganized tracks node that is having a problem.

How many rules do you have set up? I did have two, but on a hunch I decided to remove one momentarily. This changed the situation some. Clicking on the node will still result in a wait for the bar to pop up, but it does, then a few seconds later it finds the first two unorganized tracks and the bar fills roughly 1/4th of the way (an instant jump from zero to there, not a smooth increase like the other bars) full but doesn't move afterward, even after finding a view more. Once it's cycled through them all, the bar disappears. Adding the second mask back in, the behavior goes back to the original report, never moves from the starting line.

Both of these rules run on Genres (one covers all but one genre, while the other covers the one the first doesn't), and they both contain$if() statements (the first has several), so maybe those two things factor in somehow.

My Reading Tracks progress bar is working, does yours freeze, not show up??

Nyn

I seem to recall the "Reading tracks" bar on this node working in a build from the other week, however in 1201 (and I think the one just prior), it no longer shows progress. It also seems like it's performance has slowed down slightly, but that might just be my imagination.