First, thank you for this package. It is useful to have these standard elements pulled out.
The issue I'm seeing is with the customization of the Nav. The "paper" class provided through drawerStyles are breaking in the hierarchy somewhere. This code copied from the "dark theme" in Storybook.
The error I'm getting is below.
Material-UI: the key `paper` provided to the classes prop is not implemented in undefined.
You can only override one of the following: root,heightAdjustment,container,content,toggleButton,closeButton.