1. How do I add an unordered list bullet to those I've already created?

I'm assuming that you have chosen the element Unordered list on the content pane. If you need more (or less) bulleted lines, with the list selected open the right-most pane, where it says Element. At the top you have the element tree, at the bottom you will see the CSS set for the list, and in the middle, it says Selected element properties. In there you can set the number for how many bulleted lines you want to create.

Or select the last bulleted list item and then, right click and select "duplicate"