Upon further testing, enabling and disabling the shortcut in System->Preferences->Keyboard Shortcuts seems to "free up" the keyboard shortcut for the Compiz keyboard settings thing. I now can both raise and lower the window using the shortcuts defined in Compiz.
Upon further testing, enabling and disabling the shortcut in System- >Preferences- >Keyboard Shortcuts seems to "free up" the keyboard shortcut for the Compiz keyboard settings thing. I now can both raise and lower the window using the shortcuts defined in Compiz.