The tray menu opens on the wrong monitor.
If the Windows taskbar is set to the left side, and the secundary expanding monitor is set on the left side. The right-click tray menu opens on the second monitor, the one without system tray. Refer to the image attached.
I've drawn a thick black line where the monitors split.
Windows 8x64 with Greenshot 1.1.7 Build 17 (64 bit)
Windows 8x64 with 64 bit Greenshot 1.1.7 Build 17