Include any widget in a page for any theme. [do_widget widgetname ] or [do_widget "widget name" ]. If upgrading see changelog. Can be ver
Or can use [do_widget widgetname] within the text in the page and save. If the widget name has a space in it, use [do_widget "widget name"].
If you use a widget more than once for different shortcodes, you can use the widget id to isolate which widget instance (and of course associated settings to use). ie: [do_widget id=categories-6]