Enter the number of times you wish each Group to appear in the form
template. For example, in the case of "Party Identifiers", you will need
at least two Groups, since every message involves at least two parties. The maximum allowed number of repeats for each Group is shown, and a default ("1") already entered. You can take the default or enter your own value.
Groups which are indented are nested within the previous Group.
Check the box for each Segment you wish to appear a Group. Segments with no checkbox alongside are mandatory.