When running compiz.real with '--use-root-window' with nvidia 96.43.13, the directly-connect display showed update problems, that is, portions around windows and frames w/in windows would be black. The only way to correct this was to switch to another viewport and then back again. As soon as I reverted to compiz w/o '--use-root-window' and logged off and on again, everything returned to normal.
I forgot to mention:
When running compiz.real with '--use-root-window' with nvidia 96.43.13, the directly-connect display showed update problems, that is, portions around windows and frames w/in windows would be black. The only way to correct this was to switch to another viewport and then back again. As soon as I reverted to compiz w/o '--use-root-window' and logged off and on again, everything returned to normal.