Flare uses shape layers and path layers together to display vector graphics.
Vectors in Flare are rendered on shape layers. Shape layers allow you to set a Fill and Stroke colors for your paths.
The actual shape of a vector is defined by a path (or multiple paths). Expanding a shape layer in Flare will reveal the paths it's using.
In the example below, two paths are used to create a cross icon. The shape layer, named "Cross Shape" defines the fill color.