What I would like to see is an option to 'lock' images. Especially when layering images on top of each other, this would be a great feature, to prevent moving the wrong images.
This would be amazing, especially since the "undo" doesn't work if you accidentally move things. Very frustrating to have to align things over and over again.
Two years later....has this been solved in the mean time?
You can hide elements temporarily that may be obscuring other elements. While an element is hidden it cannot be moved on the canvas and is invisible.
When an element is selected it will have an eye icon on the timeline thumbnail. This eye icon is used to toggle hiding on and off.
All hidden elements can be revealed at once by clicking the double eye icon to the right of the timeline.