Date: 03/02/2013 Enhanced Folding Category List for WordPress 2.8+
The folding category plugin is very easy to install and use.
Since multi-widget administration has been overhauled, it may be necessary to reconfigure settings definitions should the plugin not be able to automatically do this for you. In most cases all you have to do is simply "save" the widget in the widgets screen and this will be enough to update the database.
If you have used the PHP code to add the widget to your page, you will have to make a slight amendment. The parameter "number" in the $instance array has been renamed to "definition". Please refer to the plugin page for detail on PHP usage.
The change was required as the old system was a bit backwards, having to select/create a "setting definition" from the widget and configure it in the admin page. This has been reversed, so that now you create and configure from the admin screen and just select the appropriate one from the widget.
Sorry for the inconvenience this may cause, but it'll be better in the long run and a requirement for some things I have in the pipeline for this plugin.