The menu is available only, if there are at least two designs.
Provide a name for the new design.
Choose an inner array and an outer array.
Decide on long or wide format.
WARNING: Currently, the functionality works well for standard situations only.
Whenever there are variables other than the factors in either of the designs
(even a block variable), problems are likely to occur at least for the
wide version designs. This will be worked on, but not top priority.