To create a new type of data structure, use the "Edit / Add structure" command. Each structure is represented as a group in the dictionary grid. Enter the members of the structure in its group the same way you enter variables in another group.
New data structures are created with default names. Use the "Edit / Rename" command to change its name.
Use the "Move Structure Up / Down" commands in the "Edit" menu to organize the list of data structures. If a member of a structure is an instance of another structure, the nested structure must be declared BEFORE in the list.