Unlike video and images, content widgets do not have a set resolution or aspect ratio. Generally, all content widgets will scale to fit to zone in which they've been programmed. However, some content widgets such as the Dynamic Track require other content, in which case the content within the widget will be scaled to fit the zone. In the case of widgets such as the "Clock" widget, it is important to be sure the size of the zone is suitable for the widget being programmed within that zone.
For example, the "Scrolling Text" widget is only suitable for zones that are long and short, often refer to as a "banner" zone.
Be sure to test content widgets on an EnGage player prior to deployment to be sure it properly fits the layout zone.