To modify a Widget in Content Central v7, you will first have to log into the Dashboard section.

In the Dashboard section of Content Central, you can use the action button (the '+' icon) at the bottom right corner to add a Widget to the Dashboard (From there you can follow the steps provided to select the Widget type and its properties). 

At the moment the following Widget types are available: Search, Folder, Coding Queue, Approval Queue, Work Queue, Checked Out, Recent Favorites.

In the Dashboard section of Content Central, once you have a Widget created, you can delete the Widget by using your mouse to drag and drop the Widget into the Trashcan icon which appears in the bottom left corner (the trashcan icon will only appear once you have begun dragging the Widget).