I have noticed an issue with the modal dialogues, but this one is a little irritating: I have tried maximizing the SMC and even stretching it to span 3 monitors before opening the broker's properties dialog hoping to see it in a corner or even behind the "Configure" window (JInternalFrame). I also tried to resize the Configure internal frame from large to very small before opening the properties dialog hoping to see it.
I fixed it by going to Tools->User Preferences->General tab and unchecking Save Window Sizes and Save Window Positions under Window Size / Position