The Polygon is a little different. You need to set the type of shape (Polygon/Star) first as well as the number of sides etc at the bottom right part of the Properties
bar. Then drag out on the canvas. To get a Star, first use the drop-down
option to set it to "Star". Then choose how many sides you want your star to have. You can also play with the angles.
For the bottom shapes, you can adjust with the yellow diamonds after you've drawn them. Here's the Star example: