Edit: I see the problem when trying to move a row in an empty folder. I will fix that. A workaround for now is to create a new row in the folder. Once the folder has a row you can move the other rows in, then remove the first row. To add a new row to a folder, the folder needs to be selected then press "Add a row".
Could you please detail more about this issue? I do not understand what do you mean with the "parallel structure". Maybe an example?