I've contacted Wacom about this but I have no idea how long it will take for them to respond. Their online contact form is utterly worthless (512 character limit?).
My Cintiq screen immediately goes black,as if it's sleeping. This problem occurred this morning. Last night when I went to bed everything was working great. I have restarted, plugged & unplugged the Cintiq, played with display options in System Preferences, nothing seems to work. The computer recognizes the Cintiq. The Cintiq just keeps going dark. When I turn it on & off, it displays for a second before going black again.