I am trying to do a somewhat of a wordpress nav loop approach, such as your loop functions show.
The code I came up with is below, and I can't seem to find why I am receiving a blank output. I am putting this album loop inside the picture page... so maybe this is why. I am trying to have a UL/LI list to the left of the single image displayed in picture.php. So what I have was derived from the album loop in the collection.php file. These files are being pulled from the default theme in plogger.
I am having this same issue. I have tried multiple combinations, even ones that I knew would not work just to see what would happen, because I have mine setup similar to yours and it shows none.