In our latest release we have made some small changes to the layout of the "Edit Assignment" page as well as introduced a new capability for creating and managing groups -

New Assignment, Copy Assignment, and Import XML are now on a separate bar instead of the bottom of the assignment list.

You can now drag and drop assignment to change their relative order. The current mechanism of selecting a position would continue to work

Please read here to learn about how to create and manage groups of assignments. This feature has been requested recently as some of the courses have a large number of assignments making it hard to manage in a flat list.