I'm new to using this program, but I think I'm encountering a bug...
I use the PopUp Choice Dialog when I create screenshots. If I click on a button that generates another SC window (Options or either of the Send to choices) the resulting window comes up behind the choice dialog... I don't know if this is normal behavior, but if it could minimize or close the choice dialog, or at least change focus and what window is on top, it would be much easier to work with. "Send via email to..." is particularly problematic, as it forces focus on that window, but the choice dialog remains on top and can't be hidden, so you can't work with the send mail window very easily.