I've been using Aperture for just under a year and love it, it's totally redone my workflow to be so much better and more productive. I have run into a question finally that I haven't been able to figure out myself.
I have a series of photos I would like to export into folders according to a metadata field I've set (and need to keep for another part of my workflow). When I export I can set the folders to be anything from times and dates and all sorts of great stuff, but I can't figure out how to make one where I can choose a metadata tag. The one I need is "Special Instructions". I can do it manually, but we're talking about 500-750 photos at a time, and it would be a lot easier if Aperture could make those folders for me.
Any other secret tricks you may know are appreciated too!

