Create a new project.
Duplicate Layout 1 twice to create Layout 2 and Layout 3.
Ctrl-Z to undo, which removes Layout 3.
Ctrl-Z again causes the following error to appear:
<img src="http://dl.dropbox.com/u/57899112/UndoBug.PNG" border="0" />
Click I for ignore and Construct 2 crashes.
Workaround is to delete the layouts instead of undoing the creation of the layouts.