A quick rotational hack
Multiple element transform via the artboard is a cool new feature of our latest public release. Currently, however, there is no rotation via the adorners. You can select multiple elements and then change their rotation simultaneously via the property inspector, but this has the downside of automatically setting all elements to have exactly the rotation you enter, regardless of their original (potentially heterogeneous) rotation. It would be nice if you could grab the corner of the multiple selection and turn it a little bit though, without all the internal shapes changing relative to each other. As a hack to get around this, you can group your elements into a canvas or grid (Object -> Group Into -> pick your favorite), and then rotate that grid/canvas/whatever. This does leave extra elements in your object stack, but you can always remove the container after the rotation; but be sure to use right click + Ungroup. This will rotate the elements relatively from where they are, since you are no longer touching them at all when you turn them.