Hey Larry,
Not so. 
Macro “Select or show a menu item” + key pressed…
I reckon you saw JM's pointer to the archive, so I won't repeat it.
That macro doesn't target a floating window. It outputs text from an Execute a Shell Script action to a Keyboard Maestro floating window.
If you want to target an OSX floating window you'll probably need to use AppleScript and System Events.
Tell me specifically what floating window you're trying to interact with, and I'll try to help.
-Chris