It would be helpful for me to choose which of the 4 corners of the window to display in. When I view Windows Picture and Fax viewer to show pictures it covers most of the buttons in the top right. If I was to set it over more (which I've already done for Trillian) It will be covering the text of dialogs, or off the left side of them. Of course the previous suggestion of excluding (or limiting) the windows it displays on, but this is another solution and something some people may appreciate.
It seems to be very unstable for me. Pretty much every reboot I have to 'end task' it. It also doesn't always exit when I select the option from the menu.