I just installed beta 19 on my win7 machine (primary, everyday use machine). Seems to work okay so far, the weird thing is that my 2ndary LCD is attached to the bottom left of my primary monitor. In addition, my win7 taskbar is vertical, on the left side of the primary monitor. Whenever I right-click the DF icon, the menubar opens inside the 2ndary monitor, which seems kind of weird. None of the other system tray icons have the same behavior.
Jon, let me know if you need any screenshots or repro steps more specific than this--not a huge issue, just seems a bit weird!