I have activated the authorize_cim plugin in Setup/Configuration, but when I save the settings the top menu does not display the plugin so that I can customize its settings. Prior to activating the plugin I did not have it added to my aMember installation, so I uploaded the authorize_cim folder to amember/plugins/payment -- this caused it to appear in the Plugins list. When I save the Plugins settings my signup pages do show Authorize CIM as a payment option, so it is active but I can't configure it. Is there another file I can re-upload to have the plugin appear in the Setup/Configuration menu?
Issue resolved. My server was missing the config.inc.php file for the Authorize CIM plugin. Lesson learned: double-check that your FTP app really does upload everything it's supposed to.