I just tried uploading 2 folders to Zenfolio using 4.6.4 public beta 4 from Vista.
Both sets of images went into the wrong folder (the last used one) instead of the one that was to be created - in that folder name I used an ampersand (&) which I can do in ZF folders - Not sure if I've ever tried to do this before.
it's still uploading so I can't try it again just yet.