I use MacOs 10.7.2 on VMware emulator. I have problem with last build of Corona 2011.704.
Corona simulator shows black screen and writes following message in terminal:

2011-12-23 14:29:02.362 Corona Simulator[221:2403] Error: Could not choose main OpenGL pixel format! Are you on a headless Mac? Please plug in a display if you are. Trying fallback, but Apple seems to have bugs with this.

What it can mean? And what to do?

Yeah, I have this problem too. I've resorted to having two virtual machines - one I use to install the latest daily builds and one with build 591 installed to use while I'm developing.

The VMWare OS X guess will never work until a graphics driver that supports QE/CI graphics is created. Apple is allowing OS X server to run virtualized now, maybe VMWare will create the needed driver.