Flak, now that you mention it, yes, that happened to me a LOT in Bryce 5. Once I had a camera setting I liked I would save it in a button setting so that when it reset I could reload it. Annoying but at least it could BE SET. In Bryce 5.5 it won't respond at all.
Dan, You've perked my curiosity... I'm not sure I ever use the Pan ICON. I'll look for that.