The new "Previous Path as a Ghost" function sounds helpful.
Because of the new File Display Border Location Bars, I've turned off the regular location bar.
In the File Display Border Location Bar, it doesn't seem that "Previous Path as a Ghost" functionality is implemented yet, or have I missed something?
Would be interested in seeing that sometime in the future. 
Working here in the new FDB...
Yeah, working here too. 
Maybe a beta 3 improvement?
Cheers steje!
Hmmm... on second thought, I've seen an issue with the new 'Reset Zoom' control that appears in the path field when you change the font scale. Sometimes it doesn't show up.
So because that's ALSO a new and unique feature in the path field, maybe there's a similar circumstance where the previous path ghost also doesn't show up. Keep an eye on it to see if it happens again and try to see if there is some pattern or action you can tie to it as the trigger.