You need to map the record itself as the "source" to the section. So
for example, if you are mapping a person record to a section named
"triResponsiblePerson"; instead of mapping the triIdTX, triNameTX,
etc. from the source record to triResponsiblePerson.triIdTX,
triResponsiblePerson.triNameTX on the target, you map the entire
person record as the source to the triResponsiblePerson section
itself. On the section title bar in the mapping dialog (right above
where the component fields are listed), if you click the magnifying
glass icon it should show "Source" as one of the options (assuming the
source record is compatible with the target section); that is the
option you want.
Eric