Mac OS X Version 10.6.2 Proc. 2.33 GHz Intel Core 2 Duo Mem. 3 GB 667 MHz DDR2 SDRAM Quartz Composer Version 4.0 (103.1) Framework Version 4.1 (156.10) Take the STANDARD screensaver with quartz composer and save it and use it as a screensaver and you get a black screen. HOWEVER it tests just perfectly normal... the way you would hope for it to work. TEST works, however when the screensaver starts, by using hot corner or just waiting for it the screen goes black. MY HYPOTHESIS - when the screensaver runs, the screen turns black, the screensaver that is trying to pull an image of the desktop is pulling that black screen image. FIX?!?!??!? I DON'T KNOW ... Of course I don't know that much about quartz composer, or creation of screensavers but such a SIMPLE thing as a blurry screen of your active desktop windows included and all is VERY confusingly difficult. PLEASE HELP ME!