It works now. Apparently, the first argument passed to the function ‘register_widget_control’ must be the same as the first argument passed to ‘register_sidebar_widget’. That makes sense to me now, since how else was WP going to know that my control went with my widget. But it didn’t seem obvious to me before, and it would’ve been nice to find it concretely stated in the widget API.
If any of the WP site admins read this, please add that little tidbit to the API docs.
These are the *only* two reasons you would not see the Presentation->Sidebar Widgets menu
There is another possibility. If one of your plugins incorrectly includes “wp-includes/widgets.php” directly, the widgets link will not show up in your administrative menu. I found this out through trial and error while trying to develop my own widget-enabled plugin.
