However, now I want to go back to the VM running in full screen mode. When I cliick in the window, the OS X dock and menu persist, covering part of the screen (including part that I want to use).
This is a known issue.
Is there a way to bring the VM to front without quitting / re-entering full-screen mode?
Click any of the icons on the right side (monitors/airport/sound/clock/fast user switch/spotlight/etc.) of the menubar.
I'll not worry about since it's a known issue. At least the icon click is a simple work-around.