You can specify a list of items as a dropdown list or checkbox list in dialogs. The values of the list must be specified in a List definition. The List definition is then referenced in the diagram, symbol, or definition where it is being used. Lists must be put in USRPROPS.TXT before any diagram, symbol, or definition entries that reference them.

Management of the USRPROPS.TXT file is easier if all List definitions are at the top of the file, after any Rename commands.