When/why would depth level custom fields be used? There must be a use for them but it beats me. 
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Hi Ciaran
A custom field can be used to record a common information requirement for the depth level. This can be used to filter records and reporting (not in all areas yet).
An example could be a field that records the location of an organisation level . The organisation hierarchy may be designed around a functional structure rather than geographic structure - adding a location field here would allow functional and a geographic stucture to be defined.
Custom fields appear in a few places to add flexibilty and can be used in reports and filters - they are optional though.Craig