Within the Styleguide you are provided with a default checklist. However, you are also given the ability to create new checklist which you are able to customize. This can be used for creating more rounded styles, or even an expandable drawer!
Rounded Checklist
To create a rounded checklist you will edit the Radius under Checkbox Styles. The higher the radius, the more rounded the edges.
You can also specify how rounded the actual box appears by editing the Radius under Box Styles.
Expandable Drawer
An expandable drawer, or accordion drop-down menu is a great feature for sharing information, such as FAQs.
To create this type of style you simply update all the sizes under Checkbox Styles to 0.