I made some additional test.
You can check this survey: https://kobo.humanitarianresponse.info/#/forms/aY9HaXhKwiJntQv4Q2Ybxu
It contains twice the same group of questions, with the rating feature and then a group of questions with the one_select mode only.
The XLS file shows that in the first case, the group has an appearance as “field-list” + one fake question with appearance as “label”, then all the sub-questions with appearance as “list-nolabel”.
The problem seems to be that the webform does not understand this appearance parameters correctly (the “label” question does not appear in the form and the sub-questions appears as if the appearance field was empty.
Best regards,
Pierre