Using this method you will only map a finite number of repetitions and ignore others. If you edit a segment definition and allow one field to repeat a finite number of times (one or more), you will be able to specifically map the repeats after you select which fields to map to which columns in your table grammar.
Group 'Message1'
Row 0
Table 'primary_id'
Row 0
ID = '583020'
Id_type = 'code1'
Table 'secondary_id'
Row 0
ID = '546'
Id_type = 'code2'