App Switcher plugin not working.

App Icons show up as expected, but clicking on them works only intermittently or not at all. ???

do you mean the predefined action "Application Switcher" or the "Show Window Switcher" actions?
(The Application Switcher action just shows the system switcher, the same that is shown when pressing cmd+tab)

Application Switcher shows currently open apps, but does not reliably switch apps when their icons are touched. Sometimes it does, sometimes it doesn't. I can get it to work more reliably by touching the icon for betterTouchTool and then the app I want to switch to, but even that is unreliable. PS, the icons respond when touched, but the app doesn't get switched.