Switch libraries by clicking on the Library Selector in SmartPanel and choosing from the list.
Find more symbols by clicking on the Library Selector and choosing More.... In the More Symbols dialog, you can use the search bar or browse the Symbol Libraries explorer tree.
You can resize shapes in several ways. Simply click on a shape to select it, then click and drag one of the black, square selection handles. To resize to a particular size, you can click on the shape's dimensions and type a new dimension, or you can select the shape and use the Position & Size group on the Design tab.
Rotate a shape using the Rotation Handle located near the border of every shape.
Simply click on the rotation handle and drag your mouse in a circular motion to rotate it, then release when it is in the desired position.
Flip a shape by clicking Flip on the Design tab and choosing Flip Vertically or Flip Horizontally. Flipping a shape produces a mirror image of the shape, so it is not the same as rotating the shape.