Since CONTRIB-3378 Collapsed Topics has had the ability to save the state of its layout in the database. This has meant the creation of bespoke course creation / restore code. This was implemented as far back as the version for Moodle 1.9. Therefore because of the change of backup / restore mechanism between 1.9 / 2.x there needs to be some conversion code as described on 'http://docs.moodle.org/dev/Backup_1.9_conversion_for_developers'.