I solved my own problem after a great deal of searching. I'm still not sure if that was a bug or if I misunderstood the resetData usage. However, for future searchers here's how I solved the problem.
On the MouseUp event, I used resetData to clear all of the text and pulldown fields (this doesn't seem to work for my image field). So then, on the Click event, I added:
ImageFieldName.rawValue = null; (where ImageFieldName is the name of the image field I want to reset)
That seemed to do the trick.
