Do I need to install the ArcFM SDK / ArcFM Development Kit to make customizations for ArcFM?
No, the core ArcFM installers install everything you need for customization development. Ensure that you select Developer Resources during install:
The ArcFM Development Kit only includes some customization samples, all of which are also available in exchange. Versions of the ArcFM Development Kit prior to 10.2.1c also included the full API documentation, but you now can access all API documentation for all versions at http://resources.arcfmsolution.com .