nofollow and another question

For (1), there is currently not a simple option for doing this, though you can do it with a YARPP custom template. https://mitcho.com/blog/projects/yarpp-3-templates/ Why do you want to do this?

For (2), you can do this with some simple CSS. You will need to find the ID of the HTML for the widget, and then modify your theme’s CSS stylesheet to specify border: 1px black solid;.