I had lots of problems with blackening of windows and immobility for a few
seconds or minutes in Gnome but then I removed LXDE and Openbox because i
suspected something. In the menu at login there was the option Gnome/Openbox but
did not work. When choosing that option t login in fact i logged into plain
gnome with Compiz. This did not happen with the earlier distros. No problem,
anyway.