Importing Child Items with excel
Wiki for this Import Child Items from MS-Excel - dRofus Wiki - dRofus Wiki (atlassian.net) is a little out of date. The import window shown does not appear to be the current version of dRofus.
Was unable able to get the upload to work through the "Import Sub Items", however I found "Belongs To" under Connections in the standard Import/Update pop up will import Child items.
I had success with dRofus finding the column "Belongs To: Item Number" automatically from excel with the standard import, however the parent item must already exist for the child item to upload to it.