If you want to add your own taxonomy elements other than elements defined in TaxonomyMapping.xml, you should follow the Replaceable Implementation approach. Current taxonomy system doesn't support hooking of partial implementation for processing your extra element. Since taxonomy system is developed based on Design by Contract principle, you can replace default implementation with custom implementation without violating the contract (i.e. strictly constrained to the interface APIs). Custom implementation is only required if the structure of the following Cúram Taxonomy files are changed, that is, adding new elements or deleting existing elements
TaxonomyTerm.xml,RelatedConcept.xml,UseReference.xml,ExternalTerm.xml
You have to provide custom implementation to the following interfaces